feat: add access control logging and feedback for increment command and button

bot.py

@@ -151,10 +151,16 @@ async def remove_counter(update: Update, context: ContextTypes.DEFAULT_TYPE):
 async def increment_counter(update: Update, context: ContextTypes.DEFAULT_TYPE):
     chat_id = update.effective_chat.id
     if not context.bot_data['access'](chat_id):
+        logger.info("Access denied for chat %s on /increment", chat_id)
+        try:
+            await update.message.reply_text("Zugriff verweigert: Dieser Chat ist nicht freigeschaltet.")
+        except Exception:
+            pass
         return
     counters = context.bot_data['counters']
     # If no argument: show inline keyboard with counters
     if not context.args:
+        logger.debug("/increment without args in chat %s -> showing keyboard (%d counters)", chat_id, len(counters))
         if not counters:
             await update.message.reply_text("Keine Counter vorhanden. Lege einen an mit /add <name>.")
             return
@@ -195,6 +201,7 @@ async def handle_increment_button(update: Update, context: ContextTypes.DEFAULT_
     counters = context.bot_data['counters']
     chat_id = query.message.chat_id if query.message else None
     if chat_id is not None and not context.bot_data['access'](chat_id):
+        logger.info("Access denied for chat %s on increment button %s", chat_id, name)
         return
     key = norm_key(name)
     if key not in counters:
@@ -202,6 +209,7 @@ async def handle_increment_button(update: Update, context: ContextTypes.DEFAULT_
         return
     counters[key] += 1
     save_counters(counters)
+    logger.debug("Increment via button: %s -> %d", key, counters[key])
     # Rebuild keyboard to reflect new values
     buttons = []
     row: list = []