The safe --fix introduced three type issues:
1. unicorn/prefer-set-has rewrote array literals to `new Set(...)`
without updating the `T[]` type annotation — broken assignment.
Fix type to `Set<T>` in logger.ts and agent-manager.ts.
2. unicorn/no-array-reverse changed `.reverse()` → `.toReversed()`
(ES2023). Bump `lib` to ES2023 in tsconfig.base.json and
tsconfig.server.json. Target stays at ES2020 — Node 20 supports
the methods natively, no downlevel needed.
3. preserve-caught-error added `new Error(msg, { cause })` (ES2022),
also covered by the lib bump.
refactor: improve agent notification types and fix activity curator
- Convert agent notifications to discriminated union (session/permission/status)
- Fix activity curator to properly handle typed session updates
- Serialize Date objects in AgentInfo for JSON compatibility
- Use activity curator for title generation context
- Reduce console.error to console.warn for non-critical WebSocket errors
- Improve spacing in agent stream views
- Delay title generation until 15+ updates available
```
