feat: initial scaffold - backend, frontend, Prisma schema, Docker

- Prisma schema: User, Session, RepoConfig, Preview, Job, WebhookToken, NoConfigComment, AdminSettings
- Backend: auth (login/logout/me/first-user setup), webhook handler with HMAC verification, EC2 service, SSH service, deploy pipeline, job queue worker, cron workers
- Frontend: Login with first-user detection, Dashboard, PreviewDetail with live log streaming, Settings, Repos config, Admin panel, SetupWizard, Privacy page
- Docker Compose and Dockerfile for self-hosted deployment
- Uses bcryptjs for Node 24 compatibility

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/tsconfig.json

@@ -0,0 +1,18 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "CommonJS",
+    "lib": ["ES2022"],
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "resolveJsonModule": true,
+    "declaration": true,
+    "declarationMap": true,
+    "sourceMap": true
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist"]
+}