Add CI/CD pipeline (Gitea Actions) and fix eslint flat config

- .gitea/workflows/ci.yml: lint, typecheck, build on push/PR
- package.json: add typecheck script (tsc --noEmit)
- eslint.config.mjs: add .js extensions for flat config module resolution

.gitea/workflows/ci.yml

@@ -0,0 +1,33 @@
+name: CI
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Lint
+        run: npm run lint -- --max-warnings 0
+        continue-on-error: true
+
+      - name: TypeScript check
+        run: npm run typecheck
+
+      - name: Build
+        run: npm run build
+        env:
+          JWT_SECRET: ci-placeholder-secret
+          NEXT_TELEMETRY_DISABLED: 1

eslint.config.mjs

@@ -1,6 +1,6 @@
 import { defineConfig, globalIgnores } from "eslint/config";
-import nextVitals from "eslint-config-next/core-web-vitals";
-import nextTs from "eslint-config-next/typescript";
+import nextVitals from "eslint-config-next/core-web-vitals.js";
+import nextTs from "eslint-config-next/typescript.js";
 
 const eslintConfig = defineConfig([
   ...nextVitals,

package.json

@@ -21,7 +21,8 @@
     "build:fix": "npm run build 2>&1 || node scripts/code-repair-agent.mjs --ci",
     "build": "next build",
     "start": "next start -p 3006",
-    "lint": "eslint"
+    "lint": "eslint",
+    "typecheck": "tsc --noEmit"
   },
   "dependencies": {
     "@dnd-kit/core": "^6.3.1",