feat: implement /show command to display full bounty details

- Add cmd_show function to display bounty details including:
  - ID and full text (not sliced)
  - Link if exists
  - Due date formatted with room timezone
  - Created by username
  - Created at timestamp
- Register show command handler in bot.py
- Add show command to help text and bot command list
- Fixes #44

apps/telegram-bot/bot.py

@@ -13,6 +13,7 @@ from commands import (
     cmd_edit,
     cmd_help,
     cmd_my,
+    cmd_show,
     cmd_start,
     cmd_timezone,
     cmd_track,
@@ -43,6 +44,7 @@ def build_app() -> Application:
     app.add_handler(CommandHandler("track", cmd_track))
     app.add_handler(CommandHandler("untrack", cmd_untrack))
     app.add_handler(CommandHandler("timezone", cmd_timezone))
+    app.add_handler(CommandHandler("show", cmd_show))
 
     app.add_handler(MessageHandler(filters.COMMAND, cmd_help))
 
@@ -59,6 +61,7 @@ async def post_init(app: Application) -> None:
             ("track", "Track a bounty"),
             ("untrack", "Stop tracking"),
             ("timezone", "Get/set room timezone"),
+            ("show", "Show bounty details"),
             ("help", "Show help"),
         ]
     )