Add CI/CD pipeline and docker-compose for deployment

- Gitea Actions workflow: test → build → push to container registry
- docker-compose.yml for host deployment (host network for PXE)
- Update example config to use container paths (/data, /etc/provisioning)

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

deploy/provisioning.example.yaml

@@ -3,18 +3,18 @@ server:
   public_url: "http://192.168.1.100:8080"
 
 database:
-  path: "./data/provisioning.db"
+  path: "/data/provisioning.db"
 
 pxe:
   enabled: true
   interface: "eth0"
   subnet: "192.168.1.0/24"
-  runtime_dir: "./data/pxe"
-  tftp_root: "./data/tftp"
+  runtime_dir: "/data/pxe"
+  tftp_root: "/data/tftp"
   dnsmasq_bin: "/usr/sbin/dnsmasq"
 
 images:
-  dir: "./data/images"
+  dir: "/data/images"
 
 proxmox:
   existing_node: "192.168.1.10"
@@ -37,4 +37,4 @@ infrastructure:
 locks:
   ttl_minutes: 60
 
-server_types_path: "./server-types.yaml"
+server_types_path: "/etc/provisioning/server-types.yaml"