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.
