fix(release): include uv.lock in release-please updates

Add uv.lock to release-please extra-files so the lockfile version is
updated alongside pyproject.toml during releases. This prevents version
drift between the published package and the lockfile.

- Add generic updater for uv.lock in release-please config
- Update uv.lock to reflect current version (2.1.1)

Author: ryoppippi

.release-please-config.json

@@ -8,7 +8,14 @@
   "include-v-in-tag": true,
   "packages": {
     ".": {
-      "package-name": "stackone-ai"
+      "package-name": "stackone-ai",
+      "extra-files": [
+        {
+          "type": "generic",
+          "path": "uv.lock",
+          "glob": false
+        }
+      ]
     }
   },
   "$schema": "https://raw.githubusercontent.com/googleapis/release-please/main/schemas/config.json"