Merge remote-tracking branch 'upstream/main'

# Conflicts:
#	apps/server/src/orchestration/decider.ts
#	apps/server/src/persistence/Migrations.ts
#	apps/web/src/components/ChatView.tsx
#	apps/web/src/components/SidebarV2.tsx
#	apps/web/src/components/chat/MessagesTimeline.tsx
#	apps/web/src/hooks/useHandleNewThread.ts

Author: eimexdev

.agents/skills/test-t3-app/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: test-t3-app
-description: Launch and test the T3 Code web app in isolated development environments, including first-try browser authentication with one-time pairing URLs, pairing-token recovery, worktree-safe state directories, dev server lifecycle, and direct SQLite inspection or fixture seeding. Use when an agent needs to run T3 locally, test UI behavior in a browser, recover from an expired or consumed pairing token, isolate dev state, or prepare test data in state.sqlite.
+description: Launch, retain, and test the T3 Code web app in isolated development environments, including first-try browser authentication with one-time pairing URLs, pairing-token recovery, worktree-safe state directories, cross-turn dev server lifecycle, and direct SQLite inspection or fixture seeding. Use when an agent needs to run T3 locally, iteratively test UI behavior with a human, recover from an expired or consumed pairing token, isolate dev state, or prepare test data in state.sqlite.
 ---
 
 # Test T3 App
@@ -20,6 +20,16 @@ Treat a base directory as disposable only when it was created or deliberately se
 
 The dev runner disables browser auto-open by default. Do not pass `--browser` during automated testing: an automatically opened page can consume the one-time bootstrap token before the controlled browser uses it.
 
+## Preserve the environment while iterating
+
+Treat the overall testing or implementation loop—not an assistant turn or one verification pass—as the environment lifecycle boundary.
+
+- Keep the dev process, base directory, selected ports, authenticated browser tab, registered projects, and seeded fixtures alive while the user may inspect the result or request follow-up changes.
+- Do not stop the server merely because one verification pass completed or because you are yielding a response to the user.
+- Before starting another environment, check whether the existing process and browser tab still serve the task. Reuse them when healthy instead of discarding useful state.
+- On a later turn, verify that the existing process is alive and reuse its printed ports and base directory. If it exited, restart with the same base directory; create a new pairing token only when the browser session is no longer valid.
+- Tell the user when a test environment remains available, including its non-secret web URL when useful. Never include a pairing token.
+
 ## Authenticate the browser on the first navigation
 
 1. Wait for the server log that says authentication is required and includes a URL ending in `/pair#token=...`.
@@ -58,9 +68,17 @@ Read [references/sqlite-fixtures.md](references/sqlite-fixtures.md) before chang
 
 The helper refuses to write to the shared `~/.t3` directory by default and creates a database backup before each mutation.
 
-## Finish the test
+## Tear down only when the testing loop is finished
+
+Tear down when the user explicitly asks, confirms the iteration is finished, or the overall task is genuinely complete with no pending human review. Do not infer completion from the end of an assistant turn.
+
+When teardown is appropriate:
+
+1. Stop the dev process with its terminal interrupt.
+2. Preserve the isolated base directory when it contains useful reproduction evidence or state for a likely follow-up.
+3. Otherwise remove only a path created for this test after resolving and verifying the exact target.
 
-Stop the dev process with its terminal interrupt. Preserve the isolated base directory when it contains useful reproduction evidence; otherwise remove only a path that was created for this test after resolving and verifying the exact target. A fresh isolated base directory is the safest reset when authentication, migrations, or fixture state becomes ambiguous.
+If completion is uncertain, keep the environment alive and mention that it is retained for further iteration. A fresh isolated base directory remains the safest reset when authentication, migrations, or fixture state becomes ambiguous.
 
 ## Troubleshoot predictably
 

.agents/skills/test-t3-app/agents/openai.yaml

@@ -1,4 +1,4 @@
 interface:
   display_name: "T3 App Testing"
-  short_description: "Launch and seed isolated T3 test environments"
-  default_prompt: "Use $test-t3-app to launch an isolated T3 development environment and test it in the browser."
+  short_description: "Launch and retain isolated T3 test environments"
+  default_prompt: "Use $test-t3-app to launch an isolated T3 environment and iteratively test it in the browser while preserving state."

apps/desktop/src/ipc/channels.ts

@@ -50,6 +50,7 @@ export const PREVIEW_ZOOM_IN_CHANNEL = "desktop:preview-zoom-in";
 export const PREVIEW_ZOOM_OUT_CHANNEL = "desktop:preview-zoom-out";
 export const PREVIEW_RESET_ZOOM_CHANNEL = "desktop:preview-reset-zoom";
 export const PREVIEW_HARD_RELOAD_CHANNEL = "desktop:preview-hard-reload";
+export const PREVIEW_SET_COLOR_SCHEME_CHANNEL = "desktop:preview-set-color-scheme";
 export const PREVIEW_OPEN_DEVTOOLS_CHANNEL = "desktop:preview-open-devtools";
 export const PREVIEW_CLEAR_COOKIES_CHANNEL = "desktop:preview-clear-cookies";
 export const PREVIEW_CLEAR_CACHE_CHANNEL = "desktop:preview-clear-cache";

apps/desktop/src/ipc/methods/preview.ts

@@ -13,6 +13,7 @@ import {
   DesktopPreviewRecordingSaveInputSchema,
   DesktopPreviewRegisterWebviewInputSchema,
   DesktopPreviewScreenshotArtifactSchema,
+  DesktopPreviewSetColorSchemeInputSchema,
   DesktopPreviewTabInputSchema,
   DesktopPreviewWebviewConfigSchema,
   PreviewAnnotationPayloadSchema,
@@ -138,6 +139,15 @@ export const hardReload = tabMethod(
   "desktop.ipc.preview.hardReload",
   (manager, tabId) => manager.hardReload(tabId),
 );
+export const setColorScheme = DesktopIpc.makeIpcMethod({
+  channel: IpcChannels.PREVIEW_SET_COLOR_SCHEME_CHANNEL,
+  payload: DesktopPreviewSetColorSchemeInputSchema,
+  result: Schema.Void,
+  handler: Effect.fn("desktop.ipc.preview.setColorScheme")(function* ({ tabId, colorScheme }) {
+    const manager = yield* PreviewManager.PreviewManager;
+    yield* manager.setColorScheme(tabId, colorScheme);
+  }),
+});
 export const openDevTools = tabMethod(
   IpcChannels.PREVIEW_OPEN_DEVTOOLS_CHANNEL,
   "desktop.ipc.preview.openDevTools",
@@ -346,6 +356,7 @@ export const methods = [
   zoomOut,
   resetZoom,
   hardReload,
+  setColorScheme,
   openDevTools,
   clearCookies,
   clearCache,

apps/desktop/src/preload.ts

@@ -160,6 +160,8 @@ contextBridge.exposeInMainWorld("desktopBridge", {
     zoomOut: (tabId) => ipcRenderer.invoke(IpcChannels.PREVIEW_ZOOM_OUT_CHANNEL, { tabId }),
     resetZoom: (tabId) => ipcRenderer.invoke(IpcChannels.PREVIEW_RESET_ZOOM_CHANNEL, { tabId }),
     hardReload: (tabId) => ipcRenderer.invoke(IpcChannels.PREVIEW_HARD_RELOAD_CHANNEL, { tabId }),
+    setColorScheme: (tabId, colorScheme) =>
+      ipcRenderer.invoke(IpcChannels.PREVIEW_SET_COLOR_SCHEME_CHANNEL, { tabId, colorScheme }),
     openDevTools: (tabId) =>
       ipcRenderer.invoke(IpcChannels.PREVIEW_OPEN_DEVTOOLS_CHANNEL, { tabId }),
     clearCookies: () => ipcRenderer.invoke(IpcChannels.PREVIEW_CLEAR_COOKIES_CHANNEL),

apps/desktop/src/preview/Manager.test.ts

@@ -365,6 +365,79 @@ describe("PreviewManager", () => {
     ),
   );
 
+  effectIt.effect("emulates prefers-color-scheme and re-applies it across webview swaps", () =>
+    withManager((manager) =>
+      Effect.gen(function* () {
+        const makeWebContents = (id: number) => {
+          const sendCommand = vi.fn(async () => undefined);
+          return {
+            sendCommand,
+            wc: {
+              id,
+              isDestroyed: () => false,
+              isDevToolsOpened: () => false,
+              getType: () => "webview",
+              getURL: () => "https://example.com",
+              getTitle: () => "Example",
+              isLoading: () => false,
+              getZoomFactor: () => 1,
+              setZoomFactor: vi.fn(),
+              on: vi.fn(),
+              off: vi.fn(),
+              ipc: { on: vi.fn(), off: vi.fn() },
+              send: webviewSend,
+              navigationHistory: { canGoBack: () => false, canGoForward: () => false },
+              setWindowOpenHandler: vi.fn(),
+              debugger: {
+                isAttached: () => false,
+                attach: vi.fn(),
+                sendCommand,
+                on: vi.fn(),
+                off: vi.fn(),
+              },
+            } as never,
+          };
+        };
+        const first = makeWebContents(42);
+        fromId.mockReturnValue(first.wc);
+        const states: PreviewManager.PreviewTabState[] = [];
+
+        yield* manager.subscribeStateChanges((_tabId, state) =>
+          Effect.sync(() => {
+            states.push(state);
+          }),
+        );
+        yield* manager.createTab("tab_scheme");
+        yield* manager.registerWebview("tab_scheme", 42);
+        yield* Effect.yieldNow;
+
+        yield* manager.setColorScheme("tab_scheme", "dark");
+
+        expect(first.sendCommand).toHaveBeenCalledWith("Emulation.setEmulatedMedia", {
+          features: [{ name: "prefers-color-scheme", value: "dark" }],
+        });
+        expect(states.at(-1)?.colorScheme).toBe("dark");
+
+        const replacement = makeWebContents(43);
+        fromId.mockReturnValue(replacement.wc);
+        yield* manager.registerWebview("tab_scheme", 43);
+        yield* Effect.yieldNow;
+
+        expect(replacement.sendCommand).toHaveBeenCalledWith("Emulation.setEmulatedMedia", {
+          features: [{ name: "prefers-color-scheme", value: "dark" }],
+        });
+        expect(states.at(-1)?.colorScheme).toBe("dark");
+
+        yield* manager.setColorScheme("tab_scheme", "system");
+
+        expect(replacement.sendCommand).toHaveBeenCalledWith("Emulation.setEmulatedMedia", {
+          features: [{ name: "prefers-color-scheme", value: "" }],
+        });
+        expect(states.at(-1)?.colorScheme).toBe("system");
+      }),
+    ),
+  );
+
   effectIt.effect("keeps a main-frame load failure visible until a retry starts", () =>
     withManager((manager) =>
       Effect.gen(function* () {

apps/desktop/src/preview/Manager.ts

@@ -7,6 +7,7 @@
  */
 import type {
   DesktopPreviewAnnotationTheme,
+  DesktopPreviewColorScheme,
   DesktopPreviewPointerEvent,
   PreviewAnnotationPayload,
   PreviewAnnotationRect,
@@ -84,6 +85,7 @@ export interface PreviewTabState {
   canGoBack: boolean;
   canGoForward: boolean;
   zoomFactor: number;
+  colorScheme: DesktopPreviewColorScheme;
   controller: "human" | "agent" | "none";
   updatedAt: string;
 }
@@ -1288,6 +1290,7 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
         canGoBack: false,
         canGoForward: false,
         zoomFactor: DEFAULT_ZOOM_FACTOR,
+        colorScheme: "system",
         controller: "none",
         updatedAt,
       };
@@ -1320,6 +1323,7 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
       canGoBack: false,
       canGoForward: false,
       zoomFactor: DEFAULT_ZOOM_FACTOR,
+      colorScheme: "system",
       controller: "none",
       updatedAt,
     };
@@ -1386,7 +1390,7 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
             wc.getZoomFactor(),
           );
     yield* attachListeners(tabId, wc);
-    runFork(ensureControlSession(wc).pipe(Effect.ignore));
+    runFork(restoreControlSession(tabId, wc));
     const registeredAt = yield* currentIso;
     const registration = yield* SynchronizedRef.modify(tabsRef, (tabs) => {
       const current = tabs.get(tabId);
@@ -1457,6 +1461,7 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
         canGoBack: current?.canGoBack ?? false,
         canGoForward: current?.canGoForward ?? false,
         zoomFactor: current?.zoomFactor ?? DEFAULT_ZOOM_FACTOR,
+        colorScheme: current?.colorScheme ?? "system",
         controller: current?.controller ?? "none",
         updatedAt,
       };
@@ -1525,7 +1530,7 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
     yield* detachControlSession(wc.id);
     yield* attempt({ operation: "openDevTools", tabId, webContentsId: wc.id }, () => {
       wc.once("devtools-closed", () => {
-        if (!wc.isDestroyed()) runFork(ensureControlSession(wc).pipe(Effect.ignore));
+        if (!wc.isDestroyed()) runFork(restoreControlSession(tabId, wc));
       });
       wc.openDevTools({ mode: "detach" });
     });
@@ -1684,6 +1689,65 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
     yield* update(tabId, { zoomFactor: next });
   });
 
+  // Emulated media lives on the CDP debugger session, not the WebContents, so
+  // it is lost whenever the session detaches (webview swap, DevTools
+  // open/close) and must be re-applied after every (re)attach.
+  const applyColorScheme = Effect.fn("PreviewManager.applyColorScheme")(function* (
+    tabId: string,
+    wc: Electron.WebContents,
+    colorScheme: DesktopPreviewColorScheme,
+  ) {
+    yield* ensureControlSession(wc);
+    yield* attemptPromise({ operation: "applyColorScheme", tabId, webContentsId: wc.id }, () =>
+      wc.debugger.sendCommand("Emulation.setEmulatedMedia", {
+        features: [
+          {
+            name: "prefers-color-scheme",
+            // An empty value clears the override so the page follows the OS.
+            value: colorScheme === "system" ? "" : colorScheme,
+          },
+        ],
+      }),
+    );
+  });
+
+  // Re-establish the control session after a detach, restoring any
+  // color-scheme override the tab carries. The scheme is read after the
+  // session attaches so a concurrent setColorScheme is not overwritten with
+  // a stale snapshot.
+  const restoreControlSession = (tabId: string, wc: Electron.WebContents) =>
+    ensureControlSession(wc).pipe(
+      Effect.andThen(SynchronizedRef.get(tabsRef)),
+      Effect.flatMap((tabs) => {
+        const colorScheme = tabs.get(tabId)?.colorScheme ?? "system";
+        return colorScheme === "system" ? Effect.void : applyColorScheme(tabId, wc, colorScheme);
+      }),
+      Effect.ignore,
+    );
+
+  const setColorScheme = Effect.fn("PreviewManager.setColorScheme")(function* (
+    tabId: string,
+    colorScheme: DesktopPreviewColorScheme,
+  ) {
+    const tab = (yield* SynchronizedRef.get(tabsRef)).get(tabId);
+    if (!tab) {
+      return yield* new PreviewTabNotFoundError({ tabId });
+    }
+    if (tab.colorScheme !== colorScheme) {
+      // Record the choice even when the CDP call below can't run yet (no
+      // webview, DevTools holding the debugger) — it is re-applied on the
+      // next control-session (re)attach.
+      yield* update(tabId, { colorScheme });
+    }
+    // Re-read after the update: registerWebview may have swapped the guest
+    // in the meantime and the override must land on the current one.
+    const webContentsId = (yield* SynchronizedRef.get(tabsRef)).get(tabId)?.webContentsId;
+    if (webContentsId == null) return;
+    const wc = webContents.fromId(webContentsId);
+    if (!wc || wc.isDestroyed()) return;
+    yield* applyColorScheme(tabId, wc, colorScheme);
+  });
+
   const captureScreenshot = Effect.fn("PreviewManager.captureScreenshot")(function* (
     tabId: string,
   ) {
@@ -2526,6 +2590,7 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
     revealArtifact,
     saveRecording,
     setAnnotationTheme,
+    setColorScheme,
     setMainWindow,
     startRecording,
     stopRecording,
@@ -2830,6 +2895,10 @@ export class PreviewManager extends Context.Service<
     readonly zoomOut: (tabId: string) => Effect.Effect<void, PreviewManagerError>;
     readonly resetZoom: (tabId: string) => Effect.Effect<void, PreviewManagerError>;
     readonly hardReload: (tabId: string) => Effect.Effect<void, PreviewManagerError>;
+    readonly setColorScheme: (
+      tabId: string,
+      colorScheme: DesktopPreviewColorScheme,
+    ) => Effect.Effect<void, PreviewManagerError>;
     readonly openDevTools: (tabId: string) => Effect.Effect<void, PreviewManagerError>;
     readonly clearCookies: () => Effect.Effect<void, PreviewManagerError>;
     readonly clearCache: () => Effect.Effect<void, PreviewManagerError>;
@@ -2921,6 +2990,7 @@ export const make = Effect.gen(function* PreviewManagerMake() {
     zoomOut: operations.zoomOut,
     resetZoom: operations.resetZoom,
     hardReload: operations.hardReload,
+    setColorScheme: operations.setColorScheme,
     openDevTools: operations.openDevTools,
     clearCookies: Effect.fn("PreviewManager.clearCookies")(function* () {
       yield* browserSession