Add security standards and CI infrastructure

- SECURITY.md with vulnerability disclosure policy and self-hosting guidance
- Dependabot config for weekly dependency updates (npm, Docker, Actions)
- ESLint v9 flat config for frontend and backend, with eslint-plugin-security
- GitHub Actions CI: lint, typecheck, build, and npm audit on every push/PR
- CodeQL workflow for automated security scanning (runs on push and weekly)

backend/package.json

@@ -7,40 +7,45 @@
     "build": "tsc",
     "start": "node dist/index.js",
     "dev": "nodemon --watch src --ext ts --exec ts-node src/index.ts",
+    "lint": "eslint src",
     "migrate": "ts-node src/db/migrate.ts"
   },
   "dependencies": {
-    "express": "^4.18.2",
-    "cors": "^2.8.5",
-    "helmet": "^7.1.0",
-    "compression": "^1.7.4",
-    "express-async-errors": "^3.1.1",
-    "jsonwebtoken": "^9.0.2",
-    "bcryptjs": "^2.4.3",
-    "pg": "^8.11.3",
     "@influxdata/influxdb-client": "^1.33.2",
-    "ioredis": "^5.3.2",
+    "bcryptjs": "^2.4.3",
     "bullmq": "^5.1.1",
+    "compression": "^1.7.4",
+    "cors": "^2.8.5",
+    "dotenv": "^16.3.1",
+    "express": "^4.18.2",
+    "express-async-errors": "^3.1.1",
+    "helmet": "^7.1.0",
+    "ioredis": "^5.3.2",
+    "jsonwebtoken": "^9.0.2",
+    "morgan": "^1.10.0",
+    "nodemailer": "^6.9.13",
+    "pg": "^8.11.3",
     "socket.io": "^4.6.1",
     "ssh2": "^1.14.0",
-    "zod": "^3.22.4",
-    "dotenv": "^16.3.1",
-    "morgan": "^1.10.0",
-    "nodemailer": "^6.9.13"
+    "zod": "^3.22.4"
   },
   "devDependencies": {
-    "@types/express": "^4.17.21",
-    "@types/cors": "^2.8.17",
-    "@types/compression": "^1.7.5",
-    "@types/jsonwebtoken": "^9.0.5",
+    "@eslint/js": "^9.39.4",
     "@types/bcryptjs": "^2.4.6",
-    "@types/pg": "^8.10.9",
-    "@types/ssh2": "^1.11.17",
+    "@types/compression": "^1.7.5",
+    "@types/cors": "^2.8.17",
+    "@types/express": "^4.17.21",
+    "@types/jsonwebtoken": "^9.0.5",
     "@types/morgan": "^1.9.9",
     "@types/node": "^20.10.5",
-    "typescript": "^5.3.3",
-    "ts-node": "^10.9.2",
+    "@types/nodemailer": "^6.4.14",
+    "@types/pg": "^8.10.9",
+    "@types/ssh2": "^1.11.17",
+    "eslint": "^9.39.4",
+    "eslint-plugin-security": "^4.0.0",
     "nodemon": "^3.0.2",
-    "@types/nodemailer": "^6.4.14"
+    "ts-node": "^10.9.2",
+    "typescript": "^5.3.3",
+    "typescript-eslint": "^8.58.2"
   }
 }