Migrate omsorgapp to browser SPA, add Docker/CI build setup

- omsorgapp: drop Electron, run as a plain Vite/React browser app; refresh
  token moves to an HttpOnly cookie (omsorgCore), CORS added for the new
  browser origin, document download/preview switched to Blob-based browser
  APIs.
- Add Dockerfiles for omsorgCore, omsorgapp, and omsorgWeb, a docker-compose.yml
  wiring Postgres/MySQL/all three apps together, and a Gitea Actions workflow
  that builds and pushes images to the repo's container registry on push to
  main and on version tags.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

omsorgapp/package.json

@@ -2,25 +2,18 @@
   "name": "omsorg-business-controls-pro",
   "version": "0.1.1",
   "private": true,
+  "type": "module",
   "description": "Omsorg Business Controls Pro - Release 0.1.1 Foundation",
-  "main": "electron/main.cjs",
   "scripts": {
-    "dev": "concurrently -k \"vite --host 127.0.0.1\" \"wait-on http://127.0.0.1:5173 && electron .\"",
-    "web": "vite --host 127.0.0.1",
-    "start": "electron ."
+    "dev": "vite --host 127.0.0.1",
+    "build": "vite build"
   },
   "dependencies": {
     "@vitejs/plugin-react": "latest",
     "vite": "latest",
-    "typescript": "latest",
     "react": "latest",
     "react-dom": "latest",
-    "electron": "latest",
     "lucide-react": "latest",
     "omsorgcore-client-ts": "file:./api-client-ts"
-  },
-  "devDependencies": {
-    "concurrently": "latest",
-    "wait-on": "latest"
   }
 }