style: auto-fix ESLint issues (curly braces and formatting)

- Add curly braces to all if/else/for/while statements
- Fix indentation and trailing spaces
- Auto-fixed 372 linting errors using eslint --fix
- Remaining issues are warnings only (non-null assertions, explicit any types)

src/session/manager.ts

@@ -13,7 +13,7 @@ export class ManagedSession implements Session {
   constructor(
     public readonly id: string,
     private store: SessionStore,
-    private history: Message[] = []
+    private history: Message[] = [],
   ) {}
 
   addMessage(message: Message): Message {
@@ -76,7 +76,7 @@ export class SessionManager {
     fromFrontend: string,
     fromUserId: string,
     toFrontend: string,
-    toUserId: string
+    toUserId: string,
   ): void {
     const fromSession = this.getSession(fromFrontend, fromUserId);
     const toSession = this.getSession(toFrontend, toUserId);