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>

Makefile

@@ -11,7 +11,7 @@ INSTALL_BIN := /usr/local/bin
 SYSTEMD_DIR := /etc/systemd/system
 ETC_DIR := /etc/xdp-defense
 DATA_DIR := /var/lib/xdp-defense
-BLOCKER_CFG := /etc/xdp-blocker
+BLOCKER_CFG := /etc/xdp-defense
 
 CLANG ?= clang
 CLANG_FLAGS := -O2 -g -Wall -target bpf \
@@ -74,7 +74,7 @@ uninstall:
 	rm -f $(INSTALL_BIN)/xdp-defense-daemon
 	rm -f $(SYSTEMD_DIR)/xdp-defense.service
 	systemctl daemon-reload
-	@echo "Uninstalled. Config preserved in $(ETC_DIR) and $(BLOCKER_CFG)"
+	@echo "Uninstalled. Config preserved in $(ETC_DIR)"
 
 enable:
 	systemctl enable xdp-defense