Add bot_config.py: single source of truth for category/feed config

Category labels, feed-file mappings, and emoji were copy-pasted across
threat_intel_bot.py, check_feeds.py, and validation/run_validation.py,
which is how the ransomware category split almost missed one of them.
check_feeds.py now imports from bot_config.py instead of keeping its
own copy.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

check_feeds.py

@@ -4,14 +4,7 @@ Quick script to check all RSS feeds status
 """
 import asyncio
 from rss_manager import RSSFeedManager
-
-CATEGORY_FEEDS = {
-    "news": "feeds/news_feeds.json",
-    "malware": "feeds/malware_feeds.json",
-    "threat_intel": "feeds/threat_intel_feeds.json",
-    "osint": "feeds/osint_feeds.json",
-    "research": "feeds/research_feeds.json",
-}
+from bot_config import CATEGORY_FEEDS
 
 async def check_all_feeds():
     totals = {}