feat(app): schedules screen - recurring agent spawns on mobile

A new Schedules tab lists every schedule across projects with its
interval, prompt, next/last run, and role/model badges; the operator
can create one (project, name prefix, interval, role, model backend,
prompt), pause/resume with a switch, and delete with confirmation.
Mirrors the web dashboard's Schedules page, including the model picker
added there. New clock/brain icons join the Lucide subset and the tab
bar grows to four tabs.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01731mKtVzsfeT4Vi3TvkR48

app/App.tsx

@@ -34,6 +34,7 @@ import { FleetScreen } from "./src/screens/FleetScreen";
 import { AgentDetailScreen } from "./src/screens/AgentDetailScreen";
 import { AnswerScreen } from "./src/screens/AnswerScreen";
 import { SpawnScreen } from "./src/screens/SpawnScreen";
+import { SchedulesScreen } from "./src/screens/SchedulesScreen";
 import { LogScreen } from "./src/screens/LogScreen";
 import { SettingsScreen } from "./src/screens/SettingsScreen";
 
@@ -46,6 +47,7 @@ function Router() {
     detail: AgentDetailScreen,
     answer: AnswerScreen,
     spawn: SpawnScreen,
+    schedules: SchedulesScreen,
     log: LogScreen,
     settings: SettingsScreen,
   }[screen];