chore(docker): centralize infrahub configuration variables

Introduces an `x-infrahub-config` extension field to the docker-compose file. This block aggregates all Infrahub environment variables (AWS, DB, Broker, Cache, etc.) into a reusable anchor (`&infrahub_config`).

This change allows for:
- Centralized management of configuration options.
- Improved visibility of available settings matching the official documentation.
- Easier injection of these variables into dependent services via the new anchor.

docker-compose.override.yml

@@ -0,0 +1,31 @@
+services:
+  # === TAILSCALE ===
+  tailscale:
+    image: tailscale/tailscale:latest
+    container_name: infrahub-tailscale
+    hostname: infrahub
+    environment:
+      - TS_AUTHKEY=${TS_AUTHKEY}
+      - TS_STATE_DIR=/var/lib/tailscale
+      - TS_SERVE_CONFIG=/config/serve-config.json
+    volumes:
+      - tailscale-state:/var/lib/tailscale
+      - ./serve-config.json:/config/serve-config.json:ro
+    cap_add:
+      - NET_ADMIN
+      - SYS_MODULE
+    restart: unless-stopped
+
+  # === Infrahub ===  
+  message-queue:
+    ports: !override
+      []
+  database:
+    ports: !override
+      []
+  infrahub-server:
+    ports: !override
+      []
+
+volumes:
+  tailscale-state: