fix: replace LLM guard with simple keyword blocklist

src/handlers/user.py

@@ -10,7 +10,7 @@ import database as db
 import rag
 import reminder as reminder_module
 import document as doc_processor
-from guard import is_academic_topic, REJECT_MESSAGE
+from guard import is_blocked, REJECT_MESSAGE
 
 _pending_confirmations: dict = {}
 REMINDER_KEYWORDS = ["ingatkan", "pengingat", "remind", "jadwalkan", "tolong ingat"]
@@ -140,7 +140,7 @@ async def ask(update: Update, context: ContextTypes.DEFAULT_TYPE):
     question = " ".join(context.args)
     await update.message.chat.send_action("typing")
 
-    if not await is_academic_topic(question, _client, DEEPSEEK_MODEL):
+    if is_blocked(question):
         await update.message.reply_text(REJECT_MESSAGE)
         return
 
@@ -330,11 +330,9 @@ async def handle_message(update: Update, context: ContextTypes.DEFAULT_TYPE):
     question = text
     await update.message.chat.send_action("typing")
 
-    # Skip guard untuk pertanyaan tentang fitur bot sendiri
-    if not is_reminder_related:
-        if not await is_academic_topic(question, _client, DEEPSEEK_MODEL):
-            await update.message.reply_text(REJECT_MESSAGE)
-            return
+    if is_blocked(question):
+        await update.message.reply_text(REJECT_MESSAGE)
+        return
 
     relevant = await rag.search(user_data["id"], question, n_results=5)
     context_text = ""