feat: implement multi-provider architecture for contribution fetching and add Docker support

docker-compose.override.yml

@@ -0,0 +1,19 @@
+# Local development overrides — picked up automatically by `docker compose up`.
+# To run with production config only: docker compose -f docker-compose.yml up
+services:
+  graph:
+    build:
+      target: dev
+    volumes:
+      - .:/app
+      - /app/vendor        # keeps vendor from the dev image, not your local dir
+    environment:
+      APP_ENV: dev
+      APP_DEBUG: "1"
+      XDEBUG_MODE: "${XDEBUG_MODE:-debug}"
+      XDEBUG_CONFIG: "client_host=host.docker.internal"
+    # Makes host.docker.internal resolve correctly on Linux
+    extra_hosts:
+      - "host.docker.internal:host-gateway"
+    ports:
+      - "9003:9003"