feat(code): migrate renderer to TanStack Router

[adamleithp]

Consolidates the TanStack Router migration stack — #2455 (file-based routing), #2456 (architectural cleanup), #2457 (navigationStore → router-derived facade) — into one PR, rebased on main and stabilized.

Why one PR instead of the stack

No layer was independently shippable: the base (#2455) failed typecheck + unit and conflicted with main, and #2457 rewrites much of what #2455/#2456 introduced. The stack gave false review granularity and 3× the CI/rebase/conflict work. Collapsing makes the broken intermediate-state failures vanish (≈2/3 of the red checks) and leaves one green CI surface + one review. Supersedes #2455, #2456, #2457.

What's in it

Migration

• File-based routing via the TanStack Router Vite plugin (autoCodeSplitting), hash history for Electron loadFile, cold-boot last-route restore.
• Deletes navigationStore + settingsDialogStore; URL is the source of truth. Transient state moves to small stores (settingsPageStore, taskInputPrefillStore).
• Settings becomes a full-page route; SettingsDialog retained for the AI-consent gate via imperative openSettingsDialog().

Stabilization (defects found shaking the stack out)

• Import cycle router → routeTree → __root → hooks → navigationBridge → router broke code-split chunks (TDZ). Added routerRef (leaf module); the bridge degrades to a no-op when the router isn't mounted instead of throwing.
• Render storm: useAppView returned a fresh object every render → SidebarMenu's [view] effect looped (markViewed ~50×/2s), starving the UI thread. Now memoized on route primitives + stable prefill ref.
• Loader hang: task-detail loader is synchronous + cache-only (can't hang the router on optimistic/cloud tasks); cold-deep-link fetch + spinner live in the component; openTask seeds the detail cache.

Per-route loading UX

• Router context: { queryClient }, createRootRouteWithContext, defaultPendingMs: 0 + defaultPendingComponent (RoutePending). Navigation commits instantly with a per-route pending slot ready for skeletons.

Merge resolution vs main

• AiApprovalScreen: kept main's in-app approve mutation + applied the store migration.
• authStore: kept main's org-switching (orgProjectsMap/switchOrg/current*), migrated switchOrg + logout off the deleted stores.
• Biome ignores the generated routeTree.gen.ts; marked linguist-generated.

Verification

• ✅ typecheck
• ✅ biome check (whole repo)
• ✅ 1594 / 1594 renderer unit tests

Follow-ups (separate PRs, post-merge)

• P0 Delete useAppView → primitive useRouterState selectors + per-route useParams (removes the render-storm class permanently).
• P1 Rip out navigationBridge → typed <Link>/useNavigate() (removes the import cycle structurally; routerRef can go).
• P1 Add defaultErrorComponent + defaultNotFoundComponent (no error boundaries today).
• P1 Roll the shared-queryOptions loader pattern + per-route skeletons across the other data routes.
• P2 Typed search params (validateSearch) to retire settingsPageStore/taskInputPrefillStore; auth as beforeLoad guards; tune defaultPendingMs.
• P3 Regression test asserting the view hook returns a stable reference; lint guard for hooks returning fresh objects.

🤖 Generated with Claude Code

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🧪 Manual testing checklist

Routing now drives app boot, auth gating, and every screen. Check each area on a fully reloaded build (Cmd+Shift+R, or restart pnpm dev:code) — HMR can't safely apply these graph changes.

App boot & route restore

• Cold start lands on /code (new-task input), no flash of the wrong screen
• Quit and relaunch restores the last route (open a task, quit, relaunch → same task)
• Last-route restore works for a deep route (e.g. /settings/environments, /skills)
• No markViewed / IPC-rate spam in the terminal at idle (render-storm regression)

Onboarding & auth gates (App.tsx gates the RouterProvider)

• Fresh/logged-out: onboarding flow renders, completes through to the app
• Auth screen → OAuth login lands in the app on /code
• Invite-code screen shows when required and proceeds after redeeming
• AI-consent gate (admin): "Approve AI data processing" button works in-app (mutation), success dismisses the gate
• AI-consent gate (non-admin): shows ask-an-admin copy, no approve button
• AI-consent gate: failure shows the error callout
• Settings opens from within the AI-consent gate (gear / shortcut)

Auth lifecycle (authStore merge with main's org-switching)

• Logout clears state and returns to the new-task screen (no hang, no "Router accessed before initialization")
• Login → project selection (multi-project account) → lands in app
• Switch org (new from main) navigates to new-task input and reloads data
  • CANT REPRO
• Select project switches and resets session correctly

New task flow (loader / storm hotspot)

• Create a task with a prompt → "Starting task…" advances to a live session (no infinite spinner)
• New task appears and persists in the sidebar list
• Create with no prompt / from a folder group works
• Failure path returns to task input with the prompt preserved
• Pending task view (/code/tasks/pending/$key) shows then transitions to the real task

Navigation between routes

• Sidebar: every item navigates (tasks, inbox, archived, skills, MCP servers, command center, settings)
• Switching between tasks is instant when cached; can navigate away mid-load (no lock)
• Space switcher / command menu navigation works
• Opening a task from the command center / task selector works
• Deleting the task you're viewing navigates you away

Per-route loading

• Cached task opens instantly (no spinner flash)
• Uncached/cold route shows the centered spinner, then content (no full-page flicker over sidebar/header)

Settings (full-page route)

• /settings redirects to /settings/general
• App chrome (header/sidebar/space-switcher) is hidden on settings
• Switching categories (general → environments → worktrees, etc.) works
• Close settings returns to the prior route via history; falls back to /code on deep-link entry
• Environments: create/edit flows (initialAction) open correctly

Deep links (warm + cold)

• Open-task deep link opens the task (cold start and while running)
• New-task deep link: new, plan, and issue actions land on task input with prefill
• Inbox deep link navigates to the inbox report
• Stale-folder task open redirects to /folders/$folderId

Other routes

• Inbox loads and signals/report interactions work
• Archived tasks load; unarchive works
• Skills page loads
• MCP servers page loads
• Command center loads and assigns tasks
• Folder settings (/folders/$folderId) loads

Regressions to watch

• No infinite re-render / UI-thread stalls anywhere (watch dev terminal for IPC-rate warnings)
• No blank screens on navigation (would indicate a thrown loader/render — note: error boundaries are a follow-up)
• Browser/router devtools show clean transitions (dev only)

[greptile-apps]

Prompt To Fix All With AI

Fix the following 3 code review issues. Work through them one at a time, proposing concise fixes.

---

### Issue 1 of 3
apps/code/src/renderer/navigationBridge.ts:48-50
The `COMMAND_CENTER_VIEWED` analytics event was tracked in the old `navigationStore.navigateToCommandCenter` action but is now silently dropped. After this PR, `COMMAND_CENTER_VIEWED` is never fired anywhere in the codebase — `navigationBridge.navigateToCommandCenter` does a bare router navigate, and the route component adds no tracking call. The `track` import and the constant are both still present in the analytics types, so no compiler error catches this.

```suggestion
export function navigateToCommandCenter(): void {
  void getRouterOrNull()?.navigate({ to: "/command-center" });
  track(ANALYTICS_EVENTS.COMMAND_CENTER_VIEWED);
}
```

### Issue 2 of 3
apps/code/src/renderer/hooks/useAppView.ts:48-55
**Stale `data` field in the task-detail branch** — `getCachedTask(taskId)` is called inside `deriveFromMatches`, which runs inside a `useMemo` that only re-computes when route primitives change (`routeId`, `taskId`, etc.). If the React Query cache for that task is updated by a poll, mutation, or subscription while the user stays on the same task-detail route, the memo won't re-fire and `view.data` will silently carry stale task data. Any consumer reading `view.data` for live content (rather than using `useTasks()` / `useQuery()` directly) will render out-of-date information. The PR description acknowledges deleting `useAppView` in a P0 follow-up; in the meantime callers should prefer `view.taskId` and their own query hooks over `view.data`.

### Issue 3 of 3
apps/code/src/renderer/hooks/useAppView.ts:22-25
**Duplicate `TaskInputReportAssociation` type** — the same interface is declared here and again in `taskInputPrefillStore.ts`. The two definitions are structurally identical today but can drift. Consider re-exporting the single canonical type from `taskInputPrefillStore.ts` (or `types.ts`) and importing it here instead.

_{Reviews (1): Last reviewed commit: "feat(code): migrate renderer to TanStack..." | Re-trigger Greptile}

[adamleithp]

Addressed the review comments in 4aec5f4f9:

• P1 — COMMAND_CENTER_VIEWED dropped: restored. navigationBridge.navigateToCommandCenter now emits it, matching the old navigationStore action. (The other event the old store fired, TASK_VIEWED, is already preserved in openTask.)
• P2 — stale AppView.data: removed the data snapshot entirely rather than carry a value that goes stale while staying on a task. HeaderRow now reads the live task via useTasks() keyed on view.taskId; useSidebarData uses view.taskId. Same cache coverage, but reactive. This also shrinks the P0 useAppView follow-up.
• P2 — duplicate TaskInputReportAssociation: useAppView now imports the canonical type from taskInputPrefillStore instead of redeclaring it.

typecheck, biome, and all 1594 unit tests green.