feat: scaffold klarbild foundation (astro+postgres+s3, auth, migrations, health)

- Astro 5 SSR (node standalone) + React, OKLCH tokens (no tailwind)
- migrations/001_init.sql: full schema per 03-datenmodell-api
- lib: db+migrations, crypto (AES-256-GCM), auth (argon2+signed session, ratelimit),
  storage (S3/MinIO, presigned URLs), openrouter (POST /v1/images, cost)
- middleware: init-once + session guard + admin gate; /api/health (db+storage)
- login + studio placeholder; seeds (till/lea, default recipes); Dockerfile
- verified: astro build passes

package.json

@@ -0,0 +1,37 @@
+{
+  "name": "klarbild",
+  "type": "module",
+  "version": "0.1.0",
+  "private": true,
+  "scripts": {
+    "dev": "astro dev",
+    "build": "astro build",
+    "start": "node ./dist/server/entry.mjs",
+    "migrate": "node --loader tsx ./scripts/migrate.mjs",
+    "astro": "astro"
+  },
+  "dependencies": {
+    "@astrojs/node": "^9.1.3",
+    "@astrojs/react": "^4.2.1",
+    "@aws-sdk/client-s3": "^3.700.0",
+    "@aws-sdk/s3-request-presigner": "^3.700.0",
+    "archiver": "^7.0.1",
+    "argon2": "^0.41.1",
+    "astro": "^5.5.0",
+    "basic-ftp": "^5.0.5",
+    "grammy": "^1.30.0",
+    "heic-convert": "^2.1.0",
+    "pg": "^8.13.1",
+    "pg-boss": "^10.1.5",
+    "react": "^19.0.0",
+    "react-dom": "^19.0.0",
+    "sharp": "^0.33.5",
+    "ssh2-sftp-client": "^11.0.0"
+  },
+  "devDependencies": {
+    "@types/pg": "^8.11.10",
+    "@types/react": "^19.0.0",
+    "@types/react-dom": "^19.0.0",
+    "typescript": "^5.7.2"
+  }
+}