fix(offline): delete a finished local game from the device, not the network

The lobby's finished-game delete (hide) always called gateway.hideGame; for a
local (offline) game the transport kill switch refused it, so it toasted and the
game stayed. Route by id: a local game is removed from the device store + the
source cache (LocalSource.delete), an online game still hides on the backend.

ui/src/lib/localgame/source.list.test.ts

@@ -65,6 +65,14 @@ describe('LocalSource.list', () => {
     expect(g.seats[1].accountId).not.toBe('acct-42'); // the robot keeps a synthetic id
   });
 
+  it('delete removes a stored local game from the list', async () => {
+    const src = new LocalSource();
+    await src.create(opts('local:x', 5n));
+    expect((await src.list()).map((g) => g.id)).toContain('local:x');
+    await src.delete('local:x');
+    expect((await src.list()).map((g) => g.id)).not.toContain('local:x');
+  });
+
   it('reconstructs a game persisted by a previous session (not in the source cache)', async () => {
     // Seed the store via one source, then list from a fresh source whose in-memory cache is empty.
     await new LocalSource().create(opts('local:old', 7n));