Unify legacy data path /etc/xdp-blocker → /etc/xdp-defense

All config/data paths now use /etc/xdp-defense/ consistently,
eliminating the legacy xdp-blocker directory reference.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/xdp_whitelist.py

@@ -11,7 +11,7 @@ from pathlib import Path
 
 from xdp_common import get_map_id, batch_map_operation, classify_cidrs
 
-WHITELIST_DIR = Path("/etc/xdp-blocker/whitelist")
+WHITELIST_DIR = Path("/etc/xdp-defense/whitelist")
 
 # Preset URLs for trusted services
 PRESETS = {