fix: cleanup codebase and sync SPEC with actual permissions

Phase 1: Ruff lint fixes
- Remove unused imports across all files
- Remove unused variables (now_utc, tz, ctx)
- Fix f-string without placeholders
- Fix E402 import order with noqa comments

Phase 2: Remove confusing hard delete from storage
- Removed delete_bounty() from RoomStorage Protocol (never used by app)
- Removed delete_bounty() from JsonFileRoomStorage (was hard delete)
- Removed corresponding tests (hard delete was never used)

Phase 3: Sync SPEC.md with actual code behavior
- Updated overview: admins can add/edit/delete (not 'anyone' + 'creator')
- Updated command table: /add, /edit, /delete are admin only
- Updated error handling messages

Test results: 96 passed (2 hard delete tests removed)

apps/telegram-bot/tests/conftest.py

@@ -1,10 +1,8 @@
 """Pytest fixtures for telegram-bot tests."""
 
 import sys
-import tempfile
 from pathlib import Path
 
-import pytest
 
 # Add the app directory to path so imports work when running pytest
 sys.path.insert(0, str(Path(__file__).parent.parent))