test(desktop): do not credit inherited coverage across a layout's early return

Ancestor resolution is static, so it credits any file under a layout that mentions a
lane-aware shell. That is wrong when the layout returns the surface *instead of* its
chrome: `workspace/[workspaceId]/layout.tsx` returns `<WorkspaceAccessDenied />` at the
top and only reaches `<WorkspaceChrome>` far below, so at runtime the denied page has no
chrome at all. The page does reserve the lane today, but a regression would have read as
inherited and passed.

`SessionExpired` is deliberately not listed: it renders as a sibling within the chrome
tree, so its inherited coverage is real. The distinction is which side of the early return
the surface sits on, not which directory it lives in.

Verified by reverting the access-denied page exactly as described — it now fails.

Author: waleedlatif1

apps/sim/app/_shell/desktop-title-bar-surfaces.test.ts

@@ -221,6 +221,22 @@ const LANE_EXEMPT_PREFIXES: Record<string, string> = {
 const isExempt = (file: string) =>
   file in LANE_EXEMPT || Object.keys(LANE_EXEMPT_PREFIXES).some((prefix) => file.startsWith(prefix))
 
+/**
+ * Surfaces a layout returns *instead of* its lane-aware chrome, not inside it.
+ *
+ * Ancestor resolution is static, so it credits any file under a layout that mentions a
+ * lane-aware shell. That is wrong for an early return: `workspace/[workspaceId]/layout.tsx`
+ * returns `<WorkspaceAccessDenied />` at the top and only reaches `<WorkspaceChrome>` much
+ * later, so at runtime the denied page has no chrome and must reserve for itself. Without
+ * this, a regression there would read as inherited and pass.
+ *
+ * `SessionExpired` is deliberately absent: it renders as a sibling *within* the chrome
+ * tree, so its inherited coverage is real.
+ */
+const SELF_RESERVE_REQUIRED = new Set([
+  'app/workspace/[workspaceId]/components/workspace-access-denied.tsx',
+])
+
 /** Every file under `app/`, so ancestor layouts can be resolved without extra fs calls. */
 const ALL_APP_FILES = new Set(
   readdirSync(new URL('../', import.meta.url), { recursive: true, encoding: 'utf8' }).map(
@@ -254,7 +270,9 @@ function viewportRoots() {
         file,
         fillsViewport: FILLS_VIEWPORT.test(source),
         self: reservesLane(source),
-        inherited: ancestorLayouts(file).some((l) => reservesLane(sourceOf(l))),
+        inherited:
+          !SELF_RESERVE_REQUIRED.has(file) &&
+          ancestorLayouts(file).some((l) => reservesLane(sourceOf(l))),
       }
     })
     .filter((r) => r.fillsViewport)