Fix critical deployment issues for Round 4

- Add DOCKER_API_VERSION=1.44 to Watchtower (fixes crash loop)
- Add dockerproxy-network creation to deploy script (fixes dashboard deployment)
- Add explicit acme.json file creation with 600 permissions (fixes SSL cert acquisition)
- Fix setup script to correctly resolve user home directory when run with sudo

These fixes resolve all critical blockers discovered in Round 3 testing.

scripts/setup-homelab.sh

@@ -162,7 +162,8 @@ generate_secret() {
 }
 
 # Check if .env file exists in the repo
-REPO_ENV_FILE="$HOME/AI-Homelab/.env"
+ACTUAL_USER_HOME=$(eval echo ~$ACTUAL_USER)
+REPO_ENV_FILE="$ACTUAL_USER_HOME/AI-Homelab/.env"
 if [ ! -f "$REPO_ENV_FILE" ]; then
     log_error ".env file not found at $REPO_ENV_FILE"
     log_info "Please create .env file from .env.example first"