feat: add settings management with username and tools context for agents

app/App.tsx

@@ -17,6 +17,7 @@ import { ThemeProvider, useTheme } from './src/theme/ThemeProvider';
 import { loadAgents } from './src/store/agentsSlice';
 import { rehydrateChat } from './src/store/chatSlice';
 import { loadChatState } from './src/store/persistence';
+import { loadSettings } from './src/store/settingsSlice';
 
 function InnerApp() {
   const { scheme, colors } = useTheme();
@@ -30,6 +31,7 @@ function InnerApp() {
       const [persisted] = await Promise.all([
         loadChatState(),
         dispatch(loadAgents()),
+        dispatch(loadSettings()),
       ]);
       if (persisted) {
         dispatch(rehydrateChat(persisted));