fix: handle asyncpg UUID in _safe_id + add cancel button to keyword input

worker/src/bot.py

@@ -33,9 +33,9 @@ def _vienna_time(dt: datetime | None, fmt: str = "%d.%m.%Y %H:%M") -> str:
     return dt.astimezone(VIENNA_TZ).strftime(fmt)
 
 
-def _safe_id(kw_id: str) -> str:
+def _safe_id(kw_id: Any) -> str:
     """Return a short, safe version of the UUID for Telegram callback_data."""
-    return kw_id[:28]  # well within 64-char limit with prefixes
+    return str(kw_id)[:28]  # handles asyncpg.UUID objects
 
 
 def _b64(text: str) -> str:
@@ -472,7 +472,12 @@ async def _handle_callback(update: Update, context: ContextTypes.DEFAULT_TYPE) -
         if sub == "add":
             context.user_data["state"] = "awaiting_keyword"
             await query.edit_message_text(
-                "Send me a search keyword (e.g. <code>rtx 3090</code>)", parse_mode="HTML")
+                "Send me a search keyword (e.g. <code>rtx 3090</code>)",
+                parse_mode="HTML",
+                reply_markup=InlineKeyboardMarkup([
+                    [InlineKeyboardButton("❌ Cancel", callback_data="cancel:menu")],
+                ]),
+            )
 
         elif sub == "list":
             subs = await pool.fetch(
@@ -519,6 +524,18 @@ async def _handle_callback(update: Update, context: ContextTypes.DEFAULT_TYPE) -
             )
             await query.edit_message_text(text=text, parse_mode="HTML")
 
+    # ════════════════════════════════════════════════════════════════════
+    # CANCEL / BACK
+    # ════════════════════════════════════════════════════════════════════
+
+    elif action == "cancel":
+        context.user_data.clear()
+        kb = _main_menu_keyboard()
+        try:
+            await query.edit_message_text("Cancelled.", reply_markup=kb, parse_mode="HTML")
+        except Exception:
+            await context.bot.send_message(chat_id=chat_id or user["telegram_id"], text="Cancelled.", reply_markup=kb)
+
     # ════════════════════════════════════════════════════════════════════
     # ADD KEYWORD FLOW
     # ════════════════════════════════════════════════════════════════════