fix(rag-api): add msgpack and confluent-kafka to requirements, safe import

- ModuleNotFoundError: No module named 'msgpack' was crashing startup
- Added msgpack>=1.0.5 and confluent-kafka>=2.3.0 to requirements.txt
- Made msgpack import safe with try/except + HAS_MSGPACK flag
- Falls back to JSON parsing if msgpack unavailable

requirements.txt

@@ -24,3 +24,5 @@ httpx>=0.27.0
 aiohttp>=3.9.0
 ddgs>=1.0.0  # Live search for hybrid RAG (renamed from duckduckgo-search)
 python-dateutil>=2.8.2    # Date parsing for live results
+msgpack>=1.0.5            # Kafka message deserialization (news.processed topic)
+confluent-kafka>=2.3.0    # Kafka consumer for top stories

src/api/routes/top_stories.py

@@ -9,12 +9,17 @@ Fast, cached, and optimized for frontend display.
 import logging
 import asyncio
 import json
-import msgpack
 from typing import List, Optional
 from fastapi import APIRouter, Query
 from pydantic import BaseModel
 from datetime import datetime
 
+try:
+    import msgpack
+    HAS_MSGPACK = True
+except ImportError:
+    HAS_MSGPACK = False
+
 logger = logging.getLogger(__name__)
 
 router = APIRouter()
@@ -158,7 +163,9 @@ def _fetch_kafka_stories_sync(n: int = 3) -> List[TopStory]:
             try:
                 value = msg.value()
                 try:
-                    event = msgpack.unpackb(value, raw=False)
+                    event = msgpack.unpackb(value, raw=False) if HAS_MSGPACK else None
+                    if event is None:
+                        raise ValueError("msgpack not available")
                 except Exception:
                     event = json.loads(value.decode("utf-8", errors="ignore"))