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/commands.py

@@ -1,8 +1,7 @@
 """Telegram command handlers for JIGAIDO - Thin wrappers around core services."""
 
 import time
-from datetime import datetime, timezone
-from functools import wraps
+from datetime import datetime
 from typing import Optional
 from zoneinfo import ZoneInfo, ZoneInfoNotFoundError
 
@@ -175,7 +174,6 @@ def format_bounty(
         except (KeyError, ZoneInfoNotFoundError):
             tz = ZoneInfo("UTC")
 
-        now_utc = int(time.time())
         dt_now = datetime.now(tz)
         dt_due = datetime.fromtimestamp(b.due_date_ts, tz=tz)
 
@@ -459,11 +457,6 @@ async def cmd_update(update: Update, ctx: ContextTypes.DEFAULT_TYPE) -> None:
 
     timezone_str = BOUNTY_SERVICE.get_timezone(room_id)
 
-    try:
-        tz = ZoneInfo(timezone_str)
-    except (KeyError, ZoneInfoNotFoundError):
-        tz = ZoneInfo("UTC")
-
     text, link, due_date_ts, clear_link, clear_date = parse_args(args[1:], timezone_str)
     if (
         not text
@@ -1034,7 +1027,7 @@ async def cmd_admin(update: Update, ctx: ContextTypes.DEFAULT_TYPE) -> None:
         ]
         reply_markup = InlineKeyboardMarkup(keyboard)
         await update.message.reply_text(
-            f"Room Admins:\n" + "\n".join(f"- {m}" for m in admin_mentions),
+            "Room Admins:\n" + "\n".join(f"- {m}" for m in admin_mentions),
             parse_mode=ParseMode.HTML,
             reply_markup=reply_markup,
         )