diff --git a/.claude/skills/ship-safely/SKILL.md b/.claude/skills/ship-safely/SKILL.md
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+---
+name: ship-safely
+description: Pre-release gate for Stroke that catches the class of bug that made v2.1.0 unquittable - Tauri ACL/capability gaps, silently swallowed IPC failures, and critical paths nobody exercised in a real build. Use before merging a `release:*` PR, after touching src-tauri/capabilities/*, window lifecycle or close/quit code in src-tauri/src/lib.rs, WindowControls.svelte or TitleBar.svelte, and whenever a change removes a handler, a tray, a menu item or a shortcut.
+---
+
+# Ship safely
+
+## Quick start
+
+```bash
+node .claude/skills/ship-safely/scripts/check-tauri-acl.mjs .
+```
+
+Exits non-zero and names the gap. Needs `src-tauri/gen/schemas/acl-manifests.json`,
+which a Tauri build writes, so run `npm run tauri dev` once on a fresh clone.
+
+## What went wrong in v2.1.0
+
+The capability file granted `core:window:allow-close` but never
+`core:window:allow-destroy`. That gap sat there harmlessly for months because
+the tray build intercepted `CloseRequested` and hid the window, so `close()`
+never ran through to `destroy`. Removing the tray let it through, the ACL
+refused the call, and the rejected promise went nowhere. The window is
+frameless with no tray, no File > Quit and no quit shortcut, so the app shipped
+with no way to close it.
+
+Three separate failures lined up. The gate below covers each one.
+
+## 1. Permissions live in a file the code does not mention
+
+`src-tauri/capabilities/default.json` is the only thing standing between a
+frontend `getCurrentWindow().x()` call and a denial, and nothing in the calling
+code points at it. Run the checker after any change to window handling, and
+read its two rules:
+
+- A JS call can require more than one permission. `close()` needs
+  **both** `allow-close` and `allow-destroy`.
+- `"windows"` is a list of label globs. `open_new_window` creates `main-2`
+  onward, and a capability scoped to `["main"]` denies every core call from
+  those windows, including dragging the title bar.
+
+## 2. A denied core call is silent in release
+
+The rejected promise had no handler, and release builds have no devtools, so
+nothing surfaced. Any call into Tauri from the UI gets awaited inside
+`try/catch` with a `console.error`, the way `WindowControls.svelte` does it now.
+Never leave `void somePromise()` on a path the user depends on.
+
+## 3. Nobody clicked the button
+
+Static checks would have caught this one, but not the next one. Exercise the
+path you changed in a running build before merging. Both of these work without
+taking over the desktop, which matters because I am usually working on it:
+
+- **Headless DOM.** With `npm run tauri dev` up, `chromium --headless=new
+  --dump-dom --virtual-time-budget=9000 http://localhost:1420/` renders the real
+  frontend. Grep the output for the state you expect.
+- **HMR self-trigger.** Temporarily call the thing on mount, save, watch the dev
+  log, revert. Back up the file first and restore from the backup, never by hand.
+
+`pcvision` screenshots of a whole monitor catch whatever else is open. Target
+the window, or use the two above.
+
+## 4. Do not remove the last way out
+
+Before deleting a tray, a menu item, a shortcut or a handler, count what is left
+for that action. The tray removal was correct on its own and only became a
+critical bug because it was the last fallback for quitting. If a change leaves
+exactly one path to something the user cannot work without, say so in the PR.
+
+## Releasing
+
+Releases run four platform builds and the org is short on Actions minutes, so
+**never merge a `release:*` PR unless I asked for a release in that message.**
+Open the PR, say the release is waiting on me, and stop. See
+`.changeset/README.md` for the changeset format.
diff --git a/.claude/skills/ship-safely/scripts/check-tauri-acl.mjs b/.claude/skills/ship-safely/scripts/check-tauri-acl.mjs
new file mode 100644
index 00000000..801fa327
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+++ b/.claude/skills/ship-safely/scripts/check-tauri-acl.mjs
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+#!/usr/bin/env node
+// Cross-references the Tauri core APIs the frontend calls against the
+// permissions src-tauri/capabilities/*.json actually grants, for every window
+// label the app creates.
+//
+// This exists because of v2.1.0: the capability file granted
+// `core:window:allow-close` but not `core:window:allow-destroy`. `close()` runs
+// through to `destroy`, the ACL refused it, the rejected promise went nowhere,
+// and the app shipped unquittable. A denied core call is silent in a release
+// build, so it has to be caught here.
+
+import { readFileSync, readdirSync, existsSync } from 'node:fs'
+import { join } from 'node:path'
+import { execSync } from 'node:child_process'
+
+const root = process.argv[2] ?? process.cwd()
+const manifestPath = join(root, 'src-tauri/gen/schemas/acl-manifests.json')
+const capsDir = join(root, 'src-tauri/capabilities')
+
+if (!existsSync(manifestPath)) {
+  console.error(`No ACL manifest at ${manifestPath}.\nRun a Tauri build once (npm run tauri dev) to generate it, then re-run.`)
+  process.exit(2)
+}
+
+const manifest = JSON.parse(readFileSync(manifestPath, 'utf8'))
+
+/** Expand one permission id into the `module:command` strings it allows. */
+function expand(module, id, seen = new Set()) {
+  const key = `${module}:${id}`
+  if (seen.has(key)) return []
+  seen.add(key)
+
+  // A fully-qualified id re-targets the module: "core:window:allow-close".
+  if (id.includes(':')) {
+    const parts = id.split(':')
+    const cmd = parts.pop()
+    return expand(parts.join(':'), cmd, seen)
+  }
+
+  const mod = manifest[module]
+  if (!mod) return []
+
+  if (id === 'default') {
+    const set = mod.default_permission
+    if (!set) return []
+    return (set.permissions ?? []).flatMap((p) => expand(module, p, seen))
+  }
+
+  const perm = mod.permissions?.[id]
+  if (perm) return (perm.commands?.allow ?? []).map((c) => `${module}:${c}`)
+
+  const set = mod.permission_sets?.[id]
+  if (set) return (set.permissions ?? []).flatMap((p) => expand(module, p, seen))
+
+  return []
+}
+
+// ── what the capabilities grant, per window label glob ──────────────────────
+const capabilities = readdirSync(capsDir)
+  .filter((f) => f.endsWith('.json'))
+  .map((f) => JSON.parse(readFileSync(join(capsDir, f), 'utf8')))
+
+const grants = capabilities.map((cap) => {
+  const allowed = new Set()
+  for (const p of cap.permissions ?? []) {
+    const id = typeof p === 'string' ? p : p.identifier
+    if (!id) continue
+    for (const c of expand('core', id)) allowed.add(c)
+    // Non-core plugins live under their own manifest key ("dialog", "opener").
+    const head = id.split(':')[0]
+    if (head !== 'core' && manifest[head]) {
+      for (const c of expand(head, id.split(':').slice(1).join(':') || 'default')) allowed.add(c)
+    }
+  }
+  return { windows: cap.windows ?? ['main'], allowed, identifier: cap.identifier }
+})
+
+const labelAllows = (glob, label) =>
+  new RegExp('^' + glob.split('*').map((s) => s.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')).join('.*') + '$').test(label)
+
+// ── what the frontend calls ─────────────────────────────────────────────────
+// JS method -> core command(s). `close` carries `destroy`: Tauri's close runs
+// through to destroy once nothing prevents it, and destroy is its own gate.
+const IMPLIED = { close: ['close', 'destroy'] }
+const camelToSnake = (s) => s.replace(/[A-Z]/g, (c) => '_' + c.toLowerCase())
+
+let hits = ''
+try {
+  hits = execSync(
+    `grep -rhoE '(getCurrentWindow|getCurrentWebviewWindow|appWindow)\\(?\\)?\\.[a-zA-Z]+' ${join(root, 'src')} || true`,
+    { encoding: 'utf8' },
+  )
+} catch { /* grep found nothing */ }
+
+const used = new Set()
+for (const line of hits.split('\n')) {
+  const m = line.match(/\.([a-zA-Z]+)$/)
+  if (!m) continue
+  const js = m[1]
+  for (const cmd of IMPLIED[js] ?? [camelToSnake(js)]) used.add(cmd)
+}
+
+// Window labels the backend creates, so second windows are checked too.
+let labels = ['main']
+try {
+  const commands = readFileSync(join(root, 'src-tauri/src/commands.rs'), 'utf8')
+  const m = commands.match(/format!\("(main-\{[a-z]+\})"\)/)
+  if (m) labels.push('main-2')
+} catch { /* no secondary windows */ }
+
+// ── report ──────────────────────────────────────────────────────────────────
+const problems = []
+for (const label of labels) {
+  const forLabel = grants.filter((g) => g.windows.some((w) => labelAllows(w, label)))
+  if (forLabel.length === 0) {
+    problems.push(`window "${label}" is covered by no capability at all - every core call from it is denied`)
+    continue
+  }
+  const allowed = new Set(forLabel.flatMap((g) => [...g.allowed]))
+  for (const cmd of [...used].sort()) {
+    if (!allowed.has(`core:window:${cmd}`) && !allowed.has(`core:webview:${cmd}`)) {
+      problems.push(`window "${label}" calls ${cmd}() but no capability grants core:window:allow-${cmd.replace(/_/g, '-')}`)
+    }
+  }
+}
+
+if (problems.length) {
+  console.error('Tauri ACL gaps:\n' + problems.map((p) => `  ✗ ${p}`).join('\n'))
+  console.error('\nAdd the permission to src-tauri/capabilities/default.json, or widen its "windows" globs.')
+  process.exit(1)
+}
+
+console.log(`Tauri ACL ok - ${used.size} core window call(s) checked across ${labels.length} window label(s): ${labels.join(', ')}`)