feat: perspectives diff view, seeded reference-architecture example, MCP perspective param (goal 0095 slice 3, ADR-0041)

frontend/bindings/github.com/alicoding/mill/internal/domain/atlas/index.ts

@@ -16,5 +16,6 @@ export type {
     MirrorContent,
     Note,
     Perspective,
+    PerspectiveDiff,
     Position
 } from "./models.js";

frontend/bindings/github.com/alicoding/mill/internal/domain/atlas/models.ts

@@ -331,6 +331,23 @@ export interface Perspective {
     "Seed": seedorigin$0.Origin;
 }
 
+/**
+ * PerspectiveDiff is the computable diff between two perspectives
+ * sharing the same live card set (ADR-0041's O(1) reference-
+ * architecture property, docs/goals/0095): pure set difference over
+ * stored membership, nothing derived or stored on disk. Re-parenting
+ * is deliberately never expressed here -- a card carries exactly one
+ * ParentID shared by every perspective, so containment itself can
+ * never differ per view (ADR-0041's own invariant; a revisit needs its
+ * own ADR).
+ */
+export interface PerspectiveDiff {
+    "AddedCardIDs": string[] | null;
+    "RemovedCardIDs": string[] | null;
+    "AddedLinkIDs": string[] | null;
+    "RemovedLinkIDs": string[] | null;
+}
+
 /**
  * Position is a card's location within its PARENT's canvas -- only
  * meaningful when the parent's EffectiveViewMode is ViewModeCanvas;

frontend/bindings/github.com/alicoding/mill/internal/services/atlassvc/atlasservice.ts

@@ -260,6 +260,19 @@ export function DetectSyncRoots(): $CancellablePromise<string[] | null> {
     return $Call.ByID(2360667167);
 }
 
+/**
+ * DiffPerspectives computes what changed moving from fromID's own
+ * membership to toID's (goal 0095 slice 3's Compare view): a thin
+ * bound wrapper over the pure atlas.DiffPerspectives helper, the same
+ * "expose the domain package's own pure function through a read-only
+ * accessor" shape Perspectives() itself already takes. Re-parenting is
+ * deliberately never expressed here -- ADR-0041's own invariant, since
+ * a card carries exactly one ParentID shared by every perspective.
+ */
+export function DiffPerspectives(fromID: string, toID: string): $CancellablePromise<atlas$0.PerspectiveDiff> {
+    return $Call.ByID(3383492038, fromID, toID);
+}
+
 /**
  * ExportAtlas serializes the whole Atlas graph as an indented, portable
  * JSON string -- share it, commit it to git, or import it into another

frontend/e2e/atlas-authoring.spec.ts

@@ -81,11 +81,15 @@ test('atlas creation core: tray, placement popover, right-click create, sticky n
     await expect(page.getByTestId('atlas-jump-no-matches')).toBeVisible()
     await page.keyboard.press('Escape')
 
+    // "My space" seeds four children (goal 0095 slice 3 added "System
+    // landscape" alongside Getting started/Example area/Scratchpad) --
+    // a hand-countable 1/4 linked, 0/4 mirrored (same census
+    // atlas-projections.spec.ts's own coverage test pins).
     await page.getByTestId('atlas-open-coverage').click()
     const coverageDialog = page.locator('[data-component="atlas-coverage-dialog"]')
     await expect(coverageDialog).toBeVisible()
-    await expect(coverageDialog.getByTestId('atlas-coverage-link-value')).toHaveText('1/3 linked')
-    await expect(coverageDialog.getByTestId('atlas-coverage-mirror-value')).toHaveText('0/3 mirrored')
+    await expect(coverageDialog.getByTestId('atlas-coverage-link-value')).toHaveText('1/4 linked')
+    await expect(coverageDialog.getByTestId('atlas-coverage-mirror-value')).toHaveText('0/4 mirrored')
     await page.keyboard.press('Escape')
     await expect(coverageDialog).not.toBeVisible()
 

frontend/e2e/atlas-breadcrumb-siblings.spec.ts

@@ -17,16 +17,17 @@ test('a breadcrumb segment opens a dropdown of its level\'s siblings, current on
 
   // "My space" is the seeded space's own root -- its siblings are
   // every other root-level card, which at the single-root default is
-  // only itself (3 top-level children: Example area, Getting started,
-  // Scratchpad).
+  // only itself. The child count is asserted as a pattern, not an
+  // exact number: seeds evolve (goal 0095 added a whole seeded area)
+  // and this test pins the dropdown's SHAPE, not the seed catalogue.
   const mySpaceCrumb = page.getByTestId('atlas-breadcrumb').getByTestId('atlas-breadcrumb-item').filter({ hasText: 'My space' })
   await mySpaceCrumb.click()
 
   const dropdown = page.getByTestId('atlas-breadcrumb-siblings')
   await expect(dropdown).toBeVisible()
   const mySpaceRow = dropdown.getByTestId('atlas-breadcrumb-sibling').filter({ hasText: 'My space' })
   await expect(mySpaceRow).toBeVisible()
-  await expect(mySpaceRow).toContainText('3 cards')
+  await expect(mySpaceRow).toContainText(/\d+ cards/)
 
   // Clicking the current place navigates to it (reproducing the old
   // direct-navigate behavior) -- the crumb collapses back to "My

frontend/e2e/atlas-gestures.spec.ts

@@ -1,7 +1,8 @@
 import { test, expect } from './fixtures/server'
 import { groupCard, noteCard } from './fixtures/atlasCards'
-import { clickCorner, zoomAllTheWayOut } from './fixtures/atlasBoard'
+import { clickCorner, zoomAllTheWayOut, clickFrameGutter } from './fixtures/atlasBoard'
 import { contextMenu } from './fixtures/contextMenu'
+import { waitForViewportStable } from './fixtures/animation'
 
 // The click model (goal 0102's gesture table) + surface-scoped
 // shortcuts (goal 0071 slice): plain click selects/replaces, a second
@@ -87,9 +88,28 @@ test('a plain click leaves the selection ring visibly showing on the clicked car
 test('a real double-click reproduces the same select-then-commit outcome as two plain clicks, for both a leaf and a frame body', async ({ page }) => {
   await page.goto('/')
   await page.getByRole('link', { name: 'Atlas' }).click()
-  await expect(page.getByTestId('atlas-board')).toBeVisible()
-
+  const board = page.getByTestId('atlas-board')
+  await expect(board).toBeVisible()
+  // The board's own initial fitView animates into place, and
+  // individual note cards carry their own entrance transition
+  // independent of the viewport's own pan/zoom transform -- a
+  // dblclick fired before BOTH settle can land on a still-moving
+  // neighbor instead of the intended card (regression: "Ada
+  // Lovelace"'s node intercepted a dblclick meant for "Getting
+  // started" while its own entrance animation was still running).
+  await waitForViewportStable(board)
   const getting = noteCard(page, 'Getting started')
+  let previousBox: string | null = null
+  await expect
+    .poll(async () => {
+      const box = await getting.boundingBox()
+      const current = box ? `${box.x},${box.y}` : null
+      const stable = previousBox !== null && current === previousBox
+      previousBox = current
+      return stable
+    })
+    .toBe(true)
+
   await getting.dblclick()
   const overlay = page.locator('[data-component="atlas-card-overlay"]')
   await expect(overlay).toBeVisible()
@@ -98,9 +118,13 @@ test('a real double-click reproduces the same select-then-commit outcome as two
   await expect(overlay).not.toBeVisible()
 
   // Frame body double-click = zoom into the place (padding strip:
-  // the frame centre belongs to its preview-child nodes).
+  // the frame centre belongs to its preview-child nodes). A FRACTION
+  // of the frame's own rendered box (not a fixed pixel offset, same
+  // idiom atlas-page.spec.ts's identical gutter click already uses)
+  // stays inside the gutter regardless of the board's own zoom scale,
+  // which shifts with the seeded card count (goal 0095 slice 3).
   const exampleArea = groupCard(page, 'Example area')
-  await exampleArea.dblclick({ position: { x: 6, y: 60 } })
+  await clickFrameGutter(exampleArea, { clickCount: 2 })
   await expect(page.getByTestId('atlas-breadcrumb')).toContainText('Example area')
 
   // ⌘↑ = one step up the depth ladder (atlas.up, Finder's enclosing-

frontend/e2e/atlas-page-edit.spec.ts

@@ -10,8 +10,7 @@ import {
 } from './fixtures/server'
 import { deleteViaPageMenu } from './fixtures/atlasPage'
 import { ATLAS_KIND_TOPIC, selectKind } from './fixtures/kindPicker'
-import { clickBreadcrumbSegment, groupCard, noteCard, openCard } from './fixtures/atlasBoard'
-import { clickAtFraction } from './fixtures/animation'
+import { clickBreadcrumbSegment, clickFrameGutter, groupCard, noteCard, openCard } from './fixtures/atlasBoard'
 
 // Atlas card page read-is-edit + chip navigation (goal 0081 slice A5,
 // LOCKED design §5b): every field editable in place with a per-save
@@ -150,7 +149,7 @@ test('atlas card page: read-is-edit fields, kind-gated mirror controls, page lin
     // edge, unclickable at a fixed fraction of its own bounding box. ---
     await page.getByRole('button', { name: 'Fit View' }).click()
     const exampleAreaFrame = groupCard(page, 'Example area')
-    await clickAtFraction(exampleAreaFrame, 0.01, 0.5, { modifiers: ['Meta'] })
+    await clickFrameGutter(exampleAreaFrame, { modifiers: ['Meta'] })
     await expect(overlay).toBeVisible()
     const childRow = overlay.getByTestId('atlas-page-child').filter({ hasText: 'Ada Lovelace' })
     await expect(childRow).toBeVisible()

frontend/e2e/atlas-page-scale.spec.ts

@@ -9,6 +9,7 @@ import {
   spawnMillServer,
   type SpawnedServer,
 } from './fixtures/server'
+import { clickFrameGutter } from './fixtures/atlasBoard'
 
 // The card PAGE at scale (goal 0073 slice B): a card holding many
 // children must cap its own Contents column the same way a board
@@ -76,14 +77,12 @@ test('a card page at scale caps its entries with an honest expander and lazy-loa
     const mirrorStack = groupCard(page, 'Mirror Stack')
     await expect(mirrorStack).toBeVisible()
 
-    // Open the page: ⌘-click on the frame's own body opens its page
-    // directly (goal 0102's gesture table's instant-commit path,
-    // atlas-page.spec.ts's own established pattern for reaching a
-    // group's page). x:6 sits inside the frame's left GROUP_PADDING
-    // gutter, a blank strip running the frame's full height below its
-    // header -- safe regardless of how many rows the 5 previewed
-    // children wrap into.
-    await mirrorStack.click({ position: { x: 6, y: 60 }, modifiers: ['Meta'] })
+    // Open the page: ⌘-click on the frame's own gutter opens its page
+    // directly (goal 0102's instant-commit path). clickFrameGutter
+    // measures a SETTLED box and a border-safe offset -- a fixed
+    // pixel position lands outside the frame once fitView zooms the
+    // denser board out further.
+    await clickFrameGutter(mirrorStack, { modifiers: ['Meta'] })
 
     const overlay = page.locator('[data-component="atlas-card-overlay"]')
     await expect(overlay).toBeVisible()
@@ -108,6 +107,9 @@ test('a card page at scale caps its entries with an honest expander and lazy-loa
   } finally {
     await browser.close()
     server?.stop()
-    rmSync(dir, { recursive: true, force: true })
+    // maxRetries: the just-stopped server can still be flushing its
+    // settings/db files when cleanup runs -- a bare rmSync races it
+    // to ENOTEMPTY.
+    rmSync(dir, { recursive: true, force: true, maxRetries: 5, retryDelay: 200 })
   }
 })

frontend/e2e/atlas-page.spec.ts

@@ -1,7 +1,6 @@
 import { test, expect } from './fixtures/server'
 import { deleteViaPageMenu } from './fixtures/atlasPage'
-import { clickAtFraction } from './fixtures/animation'
-import { armAndPlaceTopicCard, clickBreadcrumbSegment, openCard } from './fixtures/atlasBoard'
+import { armAndPlaceTopicCard, clickBreadcrumbSegment, clickFrameGutter, openCard } from './fixtures/atlasBoard'
 
 // Exercises the card PAGE's own ratified anatomy (goal 0072 slice C,
 // docs/adr/0038): the header row (kind glyph/circle, title, file tag,
@@ -189,7 +188,7 @@ test('a region frame\'s body click selects it (never drills); ⌘-click opens th
   // edge and its first column of children, running the full height
   // below the header -- a 1% fraction of width stays inside that gutter
   // whatever the board's current zoom level scales it to.
-  await clickAtFraction(exampleArea, 0.01, 0.5)
+  await clickFrameGutter(exampleArea)
   await expect(exampleAreaWrapper).toHaveCount(1)
   // The board never re-roots off a plain body click -- the header
   // remains the only unconditional drill affordance.
@@ -201,7 +200,7 @@ test('a region frame\'s body click selects it (never drills); ⌘-click opens th
   // ⌘-click opens the frame's own page directly (goal 0102's gesture
   // table: ⌘-click = instant commit, the pointer twin of ⌘↵) --
   // reached with no prior selection needed.
-  await clickAtFraction(exampleArea, 0.01, 0.5, { modifiers: ['Meta'] })
+  await clickFrameGutter(exampleArea, { modifiers: ['Meta'] })
   const overlay = page.locator('[data-component="atlas-card-overlay"]')
   await expect(overlay).toBeVisible()
   await expect(overlay.getByTestId('atlas-page-title')).toHaveValue('Example area')
@@ -252,7 +251,7 @@ test('a child\'s mirror preview renders inline in the parent page; the card\'s o
   // table's instant-commit path).
   await clickBreadcrumbSegment(page, page.getByTestId('atlas-breadcrumb').getByText('My space', { exact: true }), 'My space')
   const exampleAreaFrame = groupCard(page, 'Example area')
-  await clickAtFraction(exampleAreaFrame, 0.01, 0.5, { modifiers: ['Meta'] })
+  await clickFrameGutter(exampleAreaFrame, { modifiers: ['Meta'] })
   await expect(overlay).toBeVisible()
   await expect(overlay.getByTestId('atlas-page-title')).toHaveValue('Example area')
   const charterEntry = overlay.getByTestId('atlas-page-child').filter({ hasText: 'Project charter' })