Git browser: fix virtual portal eviction

- Frontend: `FilePane`'s "directory still exists" poll calls `pathExists` to detect externally deleted dirs (macOS FSEvents misses some deletes). Virtual `.git/<category>/...` paths don't exist on disk, so the poll evicted users back to `.git/` after 2 seconds. New `isVirtualGitPath` helper (in `file-explorer/git/path-detection.ts`) lets the poll early-return for virtual paths. Cache freshness for virtual listings already flows through `git-state-changed` and the backend's `invalidate_virtual_listings`.
- Backend: `listing/streaming.rs` started a `notify` watcher on every listing's directory. Virtual paths don't exist on disk, so `notify` errored with "No path was found" on every nav into the portal. Skip `start_watching` when `git::is_virtual(path)` — invalidation already flows through the per-repo `.git/HEAD` / `refs/` / `packed-refs` watchers.
- Verified end-to-end via the Cmdr MCP: navigated `right` pane to `.git/branches/main`, waited 8 s, pane stayed put. Backend log shows zero "Failed to watch path" warns since the rebuild.
- Tests: `path-detection.test.ts` covers each of the seven virtual categories, raw passthrough, real `.git` internals (HEAD, refs), and lookalike paths.
- Docs: updated `file-explorer/git/CLAUDE.md` and `file_system/git/CLAUDE.md` with gotchas covering both fixes.

Author: vdavid

apps/desktop/src-tauri/src/file_system/git/CLAUDE.md

@@ -307,3 +307,13 @@ runs of the test bodies themselves are fine because they only read.
 expensive call in the chip pipeline
 **Why**: On 50k files it dominates the ~60 ms total. Don't add more work
 on the chip refresh path without re-benchmarking.
+
+**Gotcha**: Listings on virtual portal paths must skip `start_watching`
+**Why**: `listing/streaming.rs` starts a `notify` watcher on the listing's
+directory. For virtual paths (`.git/branches/...` etc.) the on-disk path
+doesn't exist, so `notify` errors with "No path was found" and the warn
+log spams every navigation. The fix: skip the watcher start when
+`git::is_virtual(path)`. Cache invalidation for virtual listings flows
+through `git::watcher::invalidate_virtual_listings` (via the per-repo
+`.git/HEAD`, `refs/`, `packed-refs` watchers), so no notify watch is
+needed on the virtual side.

apps/desktop/src-tauri/src/file_system/listing/streaming.rs

@@ -504,8 +504,13 @@ pub(crate) async fn read_directory_with_progress(
         );
     }
 
-    // Get the volume from VolumeManager to check if it supports watching
-    if let Some(volume) = crate::file_system::get_volume_manager().get(volume_id)
+    // Get the volume from VolumeManager to check if it supports watching.
+    // Virtual git portal paths (`.git/branches/...` and friends) don't
+    // exist on disk, so `notify` would error with "No path was found".
+    // Cache invalidation for those listings flows through
+    // `git::watcher::invalidate_virtual_listings` instead.
+    if !crate::file_system::git::is_virtual(path)
+        && let Some(volume) = crate::file_system::get_volume_manager().get(volume_id)
         && volume.supports_watching()
         && let Err(e) = start_watching(listing_id, path)
     {

apps/desktop/src/lib/file-explorer/git/CLAUDE.md

@@ -9,14 +9,16 @@ copy via the FriendlyError pipeline.
 
 ## File map
 
-| File                    | Role                                                                                                                  |
-| ----------------------- | --------------------------------------------------------------------------------------------------------------------- |
-| `RepoChip.svelte`       | Single-line pill rendering branch + ahead/behind/dirty in the header                                                  |
-| `RepoChip.test.ts`      | Snapshot-style tests for the six visual states                                                                        |
-| `git-store.svelte.ts`   | Per-repo reactive `RepoInfo` map. `subscribeToRepo(repoRoot)` is the live channel; `lookupRepoInfo(path)` is one-shot |
-| `status-column.ts`      | Pure helpers: `glyphFor`, `labelFor`, `fetchStatusMap`. No reactivity                                                 |
-| `status-column.test.ts` | Tests for `glyphFor`, `labelFor`, and `fetchStatusMap` (mocks the IPC envelope)                                       |
-| `git-store.test.ts`     | Tests for refcounted subscribe/unsubscribe and `lookupRepoInfo` envelope unwrapping                                   |
+| File                     | Role                                                                                                                                                                       |
+| ------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `RepoChip.svelte`        | Single-line pill rendering branch + ahead/behind/dirty in the header                                                                                                       |
+| `RepoChip.test.ts`       | Snapshot-style tests for the six visual states                                                                                                                             |
+| `git-store.svelte.ts`    | Per-repo reactive `RepoInfo` map. `subscribeToRepo(repoRoot)` is the live channel; `lookupRepoInfo(path)` is one-shot                                                      |
+| `status-column.ts`       | Pure helpers: `glyphFor`, `labelFor`, `fetchStatusMap`. No reactivity                                                                                                      |
+| `status-column.test.ts`  | Tests for `glyphFor`, `labelFor`, and `fetchStatusMap` (mocks the IPC envelope)                                                                                            |
+| `git-store.test.ts`      | Tests for refcounted subscribe/unsubscribe and `lookupRepoInfo` envelope unwrapping                                                                                        |
+| `path-detection.ts`      | `isVirtualGitPath(path)` — shared regex matching the seven backend `Cat` segments. Used to skip filesystem-bound polls (and future similar checks) on virtual portal paths |
+| `path-detection.test.ts` | Tests for `isVirtualGitPath` (each category, raw passthrough, real `.git` internals, lookalikes)                                                                           |
 
 ## Lifecycle
 
@@ -76,6 +78,12 @@ information gain. We treat the user setting as "show when meaningful" rather tha
 
 ## Gotchas
 
+**Gotcha**: `FilePane`'s "directory still exists" poll evicts users back to `.git/` on virtual paths if not skipped.
+**Why**: `pathExists(currentPath)` returns false for `.git/branches/main/...` because those paths only exist in the
+portal, not on disk. After two consecutive false readings the poll calls `navigateToFallback`. The poll body now early-
+returns via `isVirtualGitPath(currentPath)` so virtual paths stay put. Cache freshness for virtual listings already
+flows through `git-state-changed` and the backend's `invalidate_virtual_listings`.
+
 ## Redirect navigation (M3)
 
 `FileEntry.redirectToPath` is honoured in `FilePane.svelte::handleNavigate`. When set, opening the entry navigates to

apps/desktop/src/lib/file-explorer/git/path-detection.test.ts

@@ -0,0 +1,62 @@
+import { describe, it, expect } from 'vitest'
+import { isVirtualGitPath } from './path-detection'
+
+describe('isVirtualGitPath', () => {
+  it('treats the `.git` directory itself as real', () => {
+    expect(isVirtualGitPath('/Users/me/repo/.git')).toBe(false)
+  })
+
+  it('treats raw `.git` internals as real', () => {
+    // `.git/HEAD` and `.git/refs/...` are real on-disk files. Only the
+    // seven category names route to the virtual portal.
+    expect(isVirtualGitPath('/Users/me/repo/.git/HEAD')).toBe(false)
+    expect(isVirtualGitPath('/Users/me/repo/.git/refs/heads/main')).toBe(false)
+    expect(isVirtualGitPath('/Users/me/repo/.git/objects/pack')).toBe(false)
+    expect(isVirtualGitPath('/Users/me/repo/.git/config')).toBe(false)
+  })
+
+  it('detects each of the seven virtual categories', () => {
+    const root = '/Users/me/repo/.git'
+    expect(isVirtualGitPath(`${root}/branches`)).toBe(true)
+    expect(isVirtualGitPath(`${root}/tags`)).toBe(true)
+    expect(isVirtualGitPath(`${root}/commits`)).toBe(true)
+    expect(isVirtualGitPath(`${root}/stash`)).toBe(true)
+    expect(isVirtualGitPath(`${root}/worktrees`)).toBe(true)
+    expect(isVirtualGitPath(`${root}/submodules`)).toBe(true)
+    expect(isVirtualGitPath(`${root}/raw`)).toBe(true)
+  })
+
+  it('detects subpaths inside a virtual category', () => {
+    expect(isVirtualGitPath('/Users/me/repo/.git/branches/main')).toBe(true)
+    expect(isVirtualGitPath('/Users/me/repo/.git/branches/main/src/foo.rs')).toBe(true)
+    expect(isVirtualGitPath('/Users/me/repo/.git/branches/feature/foo')).toBe(true)
+    expect(isVirtualGitPath('/Users/me/repo/.git/tags/v1.0.0')).toBe(true)
+    expect(isVirtualGitPath('/Users/me/repo/.git/commits/abc123/Cargo.toml')).toBe(true)
+  })
+
+  it('treats the `raw` passthrough as virtual even though contents are real-FS', () => {
+    // `raw/` routes through `list_raw` in the backend; conceptually the
+    // path is still part of the portal, so frontend FS-bound polls
+    // should skip it.
+    expect(isVirtualGitPath('/Users/me/repo/.git/raw/HEAD')).toBe(true)
+    expect(isVirtualGitPath('/Users/me/repo/.git/raw/refs/heads/main')).toBe(true)
+  })
+
+  it('ignores paths that look similar but are not under `.git`', () => {
+    expect(isVirtualGitPath('/Users/me/projects/branches/main')).toBe(false)
+    expect(isVirtualGitPath('/Users/me/repo/git/branches/main')).toBe(false)
+    expect(isVirtualGitPath('/Users/me/repo/.gitignore')).toBe(false)
+  })
+
+  it('returns false for normal paths', () => {
+    expect(isVirtualGitPath('/Users/me/foo/bar')).toBe(false)
+    expect(isVirtualGitPath('/')).toBe(false)
+    expect(isVirtualGitPath('')).toBe(false)
+  })
+
+  it('does not match when the segment after `.git/` only starts with a category name', () => {
+    // Exact category match required: `.git/branches-of-foo` is not virtual.
+    expect(isVirtualGitPath('/Users/me/repo/.git/branches-of-foo')).toBe(false)
+    expect(isVirtualGitPath('/Users/me/repo/.git/raw_logs')).toBe(false)
+  })
+})

apps/desktop/src/lib/file-explorer/git/path-detection.ts

@@ -0,0 +1,29 @@
+/**
+ * Shared helper for spotting paths inside the virtual `.git` portal.
+ *
+ * The backend exposes seven categories under `.git/`: `branches`, `tags`,
+ * `commits`, `stash`, `worktrees`, `submodules`, and `raw`. Subpaths that
+ * route through any of these are virtual — they don't exist on disk in the
+ * shape Cmdr presents them. The `.git` directory itself (and other real
+ * `.git/` internals like `HEAD` or `refs/heads/main`) stay real.
+ *
+ * The frontend uses this to skip filesystem-bound bookkeeping (the
+ * "directory still exists" poll, future similar checks) on virtual paths.
+ *
+ * The seven category names mirror `Cat` in
+ * `apps/desktop/src-tauri/src/file_system/git/path.rs`. Keep them in sync.
+ */
+
+const VIRTUAL_GIT_CATEGORIES = ['branches', 'tags', 'commits', 'stash', 'worktrees', 'submodules', 'raw'] as const
+
+const VIRTUAL_GIT_PATH_REGEX = new RegExp(`/\\.git/(?:${VIRTUAL_GIT_CATEGORIES.join('|')})(?:/|$)`)
+
+/**
+ * Returns `true` when `path` lives under one of the seven virtual git
+ * categories. Returns `false` for the `.git` root itself, for raw git
+ * internals like `.git/HEAD` or `.git/refs/heads/main`, and for normal
+ * non-git paths.
+ */
+export function isVirtualGitPath(path: string): boolean {
+  return VIRTUAL_GIT_PATH_REGEX.test(path)
+}

apps/desktop/src/lib/file-explorer/pane/FilePane.svelte

@@ -65,6 +65,7 @@
     import { splitPathSegments } from '../navigation/path-segments'
     import RepoChip from '../git/RepoChip.svelte'
     import { lookupRepoInfo, subscribeToRepo, unsubscribeFromRepo, type RepoInfo } from '../git/git-store.svelte'
+    import { isVirtualGitPath } from '../git/path-detection'
     import { getSetting, onSpecificSettingChange } from '$lib/settings'
     import ErrorPane from './ErrorPane.svelte'
     import VolumeUnreachableBanner from './VolumeUnreachableBanner.svelte'
@@ -1845,6 +1846,12 @@
         // Poll to detect externally deleted directories (macOS FSEvents doesn't notify)
         dirExistsPollInterval = setInterval(() => {
             if (!listingId || loading || isNetworkView || isMtpView) return
+            // Virtual `.git/<category>/...` paths don't exist on disk, so
+            // `pathExists` always returns false and the poll would evict
+            // the user back to `.git/`. The git watcher keeps these
+            // listings fresh via `git-state-changed` and the
+            // `directory-diff` events from `invalidate_virtual_listings`.
+            if (isVirtualGitPath(currentPath)) return
             void pathExists(currentPath).then((exists) => {
                 if (exists) {
                     dirNotExistsCount = 0