chore(release): bump version to 0.9.19-rc.4

- Add production Docker Compose configuration

- Add check_auth.py diagnostic script for session 401 debugging

frontend/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "bangui-frontend",
-  "version": "0.9.19",
+  "version": "0.9.19-rc.4",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "bangui-frontend",
-      "version": "0.9.19",
+      "version": "0.9.19-rc.4",
       "dependencies": {
         "@fluentui/react-components": "^9.55.0",
         "@fluentui/react-icons": "^2.0.257",