fix: declare cell-network external; pre-create in Makefile start/update

Docker Compose v5 enforces label ownership on networks it creates. On
systems where cell-network was created by an older compose version (no
labels), Caddy and other services fail to start with "incorrect label"
error.

Declaring the network external in docker-compose.yml skips label
validation. The Makefile start/update targets now create the network if
it doesn't exist (idempotent). The reinstall and uninstall (full) paths
explicitly delete the network so fresh recreations are clean.

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

Makefile

@@ -102,6 +102,8 @@ init-peers:
 
 start:
 	@echo "Starting Personal Internet Cell..."
+	@docker network inspect cell-network >/dev/null 2>&1 || \
+	  docker network create --driver bridge --subnet "$${CELL_NETWORK:-172.20.0.0/16}" cell-network
 	PUID=$$(id -u) PGID=$$(id -g) $(DCF) --profile core up -d --build
 	@echo "Services started. Check status with 'make status'"
 
@@ -141,12 +143,15 @@ update:
 	git pull
 	@git stash pop --quiet 2>/dev/null || true
 	@echo "Rebuilding and restarting services..."
+	@docker network inspect cell-network >/dev/null 2>&1 || \
+	  docker network create --driver bridge --subnet "$${CELL_NETWORK:-172.20.0.0/16}" cell-network
 	PUID=$$(id -u) PGID=$$(id -g) $(DCF) --profile core up -d --build
 	@echo "Update complete. Run 'make status' to verify."
 
 reinstall:
 	@echo "Reinstalling Personal Internet Cell from scratch..."
-	PUID=$$(id -u) PGID=$$(id -g) $(DCF) --profile core down -v 2>/dev/null || true
+	PUID=$$(id -u) PGID=$$(id -g) $(DCF) --profile core down 2>/dev/null || true
+	docker network rm cell-network 2>/dev/null || true
 	@sudo rm -rf config/ data/
 	@$(MAKE) setup
 	@$(MAKE) start
@@ -176,7 +181,8 @@ uninstall:
 	  y|Y) \
 	    echo "Stopping containers and removing images..."; \
 	    for f in data/services/*/docker-compose.yml; do [ -f "$$f" ] && PUID=$$(id -u) PGID=$$(id -g) docker compose -f "$$f" down 2>/dev/null || true; done; \
-	    PUID=$$(id -u) PGID=$$(id -g) $(DCF) --profile core down -v --rmi all 2>/dev/null || true; \
+	    PUID=$$(id -u) PGID=$$(id -g) $(DCF) --profile core down --rmi all 2>/dev/null || true; \
+	    docker network rm cell-network 2>/dev/null || true; \
 	    echo "Deleting config/ and data/..."; \
 	    sudo rm -rf config/ data/; \
 	    echo "Uninstall complete. Git repo and scripts remain."; \

docker-compose.yml

@@ -181,7 +181,4 @@ services:
 networks:
   cell-network:
     name: cell-network
-    driver: bridge
+    external: true
-    ipam:
-      config:
-        - subnet: ${CELL_NETWORK:-172.20.0.0/16}