fix(app-shell): keep the declared home when no package is left after a delete

Narrows the previous commit to the list[0] arm. With no package left,
the eviction still lands on useHomePath()'s declared home, the
recovery exit the home-path source scan pins for this site; only the
"a sibling survives" case moves to the Studio landing. The two
"nothing left" deletion pins are back to their original text and stay
as controls.

Claude-Session: https://claude.ai/code/session_01CGZy1BGCjdN5cXqL9cnvB8
Co-authored-by: Claude <noreply@anthropic.com>

Author: claude

.changeset/11784-package-delete-confirm.md

@@ -13,8 +13,8 @@ also drops the object tables.
 
 After deleting the package that is open in Studio, Studio now returns to its landing (`/studio`),
 where the next package can be picked or a new one created. It used to open whichever package the
-list started with, or, with no package left, leave Studio for the home page. The console's Packages
-page is unchanged: a delete there reloads the list in place.
+list started with. With no package left at all it still goes to the home page, as before. The
+console's Packages page is unchanged: a delete there reloads the list in place.
 
 Discard changes (N) used to discard every pending draft at once. It now asks first, naming the count.
 

packages/app-shell/src/views/studio-design/StudioDesignSurface.packageDeletionInference.test.tsx

@@ -33,13 +33,13 @@
  *      degrade into "never navigate", which strands the author on a package
  *      that no longer exists.
  *
- * Where a REAL deletion lands changed with objectui#11784 (triage comment
- * 6041966855: "return to `/studio` after a delete"): the Studio landing,
- * whatever is left. It used to open `list[0]` — whichever package the list
- * started with, so a delete read as "Studio moved me into another app" — or,
- * with nothing left, the home path. The three REAL-deletion cases below say
- * the new destination; the FAILED-refresh cases and the "package still there"
- * case are unchanged, as controls.
+ * Where a REAL deletion lands while other packages remain changed with
+ * objectui#11784 (triage comment 6041966855: "return to `/studio` after a
+ * delete"): the Studio landing. It used to open `list[0]`, whichever package
+ * the list started with, so a delete read as "Studio moved me into another
+ * app". The "sibling survives" case says the new destination; every other case
+ * here is unchanged and stays as a control, the two "nothing left" cases
+ * included (that arm is still objectui#7373's declared home).
  *
  * ⛔ The `.catch` is deliberately still a `.catch` (one 503 must not take the
  * Studio down — objectui#7368's ruling) and there is deliberately still no
@@ -301,28 +301,24 @@ describe('Studio package lifecycle — a failed refresh is not a deletion (#7821
     expect(await screen.findByText('Packages (apps)')).toBeInTheDocument();
   });
 
-  it('REAL deletion, nothing left: returns to the Studio landing, not /home (objectui#11784)', async () => {
+  it('REAL deletion, nothing left: still navigates to /home (behaviour unchanged)', async () => {
     const lifecycle = await openLifecycleSheet();
 
     // The list came back — successfully — and the package is gone from it.
     fetchPackagesMock.mockResolvedValue([]);
     fireEvent.click(lifecycle);
 
-    // Triage 6041966855: "return to `/studio` after a delete". The landing
-    // needs no package to open; it offers "New package".
-    expect(await screen.findByTestId('studio-landing')).toBeInTheDocument();
-    expect(where()).toBe('/studio');
-    expect(screen.queryByTestId('home-page')).not.toBeInTheDocument();
+    expect(await screen.findByTestId('home-page')).toBeInTheDocument();
+    expect(where()).toBe('/home');
     // A successful refresh is not a failure: nothing was reported.
     expect(toastError).not.toHaveBeenCalled();
   });
 
-  it('REAL deletion, nothing left, a DECLARED landing: still the Studio landing, never the launcher (objectui#11784, objectui#7373)', async () => {
+  it('REAL deletion, nothing left, a DECLARED landing: evicts to it, not to the launcher (objectui#7373)', async () => {
     // Same eviction as the case above — the only difference is that this
-    // deployment declares where home is. objectui#7373 kept this eviction out
-    // of the environment launcher by following the declared landing; since
-    // objectui#11784 (triage 6041966855: "return to `/studio` after a delete")
-    // it does not leave Studio at all, so neither home is consulted.
+    // deployment declares where home is. Pre-#7373 the destination was the
+    // `/home` literal either way, which on a control plane drops the author
+    // into the environment launcher.
     const lifecycle = await openLifecycleSheet([row(PACKAGE_ID)], [
       { name: 'cloud_control', label: 'Cloud', isDefault: true },
       { name: 'account', label: 'Account' },
@@ -331,25 +327,22 @@ describe('Studio package lifecycle — a failed refresh is not a deletion (#7821
     fetchPackagesMock.mockResolvedValue([]);
     fireEvent.click(lifecycle);
 
-    expect(await screen.findByTestId('studio-landing')).toBeInTheDocument();
-    expect(where()).toBe('/studio');
-    expect(screen.queryByTestId('declared-landing')).not.toBeInTheDocument();
-    expect(screen.queryByTestId('home-page')).not.toBeInTheDocument();
+    expect(await screen.findByTestId('declared-landing')).toBeInTheDocument();
+    expect(where()).toBe('/apps/cloud_control');
     expect(toastError).not.toHaveBeenCalled();
   });
 
   it('REAL deletion, a sibling survives: returns to the Studio landing, not into the sibling (objectui#11784)', async () => {
     // The card's measured complaint: after the delete, Studio landed on
-    // another package (showcase) — `list[0]` — instead of the Studio landing.
-    // Triage 6041966855: "return to `/studio` after a delete".
+    // another package (showcase), the list's first entry, instead of the
+    // Studio landing. Triage 6041966855: "return to `/studio` after a delete".
     const lifecycle = await openLifecycleSheet([row(PACKAGE_ID), row(SIBLING_ID)]);
 
     fetchPackagesMock.mockResolvedValue([row(SIBLING_ID)]);
     fireEvent.click(lifecycle);
 
     expect(await screen.findByTestId('studio-landing')).toBeInTheDocument();
     expect(where()).toBe('/studio');
-    expect(where()).not.toBe(`/studio/${SIBLING_ID}/interfaces`);
     expect(screen.queryByTestId('home-page')).not.toBeInTheDocument();
   });
 

packages/app-shell/src/views/studio-design/StudioDesignSurface.tsx

@@ -431,6 +431,10 @@ function PackageSwitcher({
 }): React.ReactElement {
   const navigate = useNavigate();
   const locale = useMetadataLocale();
+  // objectui#7373 — where the deleted-package eviction below lands when no
+  // other package is left to open: the DECLARED landing, the launcher only when
+  // the deployment declares none.
+  const homePath = useHomePath();
   const [open, setOpen] = React.useState(false);
   const [pkgs, setPkgs] = React.useState<PkgEntry[] | null>(null);
   /**
@@ -658,7 +662,8 @@ function PackageSwitcher({
 
   // A lifecycle action ran in the sheet — refresh the list AND the managed
   // snapshot (so an edit shows immediately). If the managed package was the one
-  // we're editing and it's now gone (deleted), return to the Studio landing.
+  // we're editing and it's now gone (deleted), return to the Studio landing
+  // (home, when no package is left).
   const onManageChanged = React.useCallback(async () => {
     /**
      * `null` means "the refresh did not tell us anything", which is NOT the
@@ -699,12 +704,15 @@ function PackageSwitcher({
     // either way: the author stays put, and the managed snapshot below is
     // still refreshed (that call reports its own outcome).
     if (list !== null && !list.some((p) => p.id === managedId)) {
-      // Deleted — only navigate away if it was the package we're editing, and
-      // then to the Studio landing (objectui#11784), where the author picks the
-      // next package or creates one. This used to open `list[0]` — whichever
-      // package the list happened to start with, so a delete read as "Studio
-      // moved me into another app" — or, with nothing left, the home path.
-      if (managedId === packageId) navigate('/studio');
+      // Deleted — only navigate away if it was the package we're editing.
+      // While other packages remain, that is the Studio landing
+      // (objectui#11784), where the author picks the next one or creates one;
+      // this used to open `list[0]`, whichever package the list started with,
+      // so a delete read as "Studio moved me into another app". With nothing
+      // left it is still the declared home (objectui#7373).
+      if (managedId === packageId) {
+        navigate(list.length > 0 ? '/studio' : homePath);
+      }
       return;
     }
     /**
@@ -782,7 +790,7 @@ function PackageSwitcher({
       );
       setManageOpen(false);
     }
-  }, [manage, packageId, navigate, fetchFullPackage, locale]);
+  }, [manage, packageId, navigate, fetchFullPackage, locale, homePath]);
 
   return (
     // Radix Popover (portaled to <body>) — the top bar is `overflow-x-auto`,