feat(app): memory screen - browse the agent note graph on mobile

A new Memory tab loads /memory/graph when opened and lists the
distilled notes newest-first with kind filter chips
(fact/decision/gotcha/runbook); tapping a note expands its body, tags,
and both directions of its links, resolved to note titles. Read-only by
design — authoring stays with the web dashboard's admin surface and the
agents' own MCP server.

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

app/App.tsx

@@ -35,6 +35,7 @@ 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 { MemoryScreen } from "./src/screens/MemoryScreen";
 import { LogScreen } from "./src/screens/LogScreen";
 import { SettingsScreen } from "./src/screens/SettingsScreen";
 
@@ -48,6 +49,7 @@ function Router() {
     answer: AnswerScreen,
     spawn: SpawnScreen,
     schedules: SchedulesScreen,
+    memory: MemoryScreen,
     log: LogScreen,
     settings: SettingsScreen,
   }[screen];