set up new workflow and migrate to .forgejo dir

.forgejo/workflows/deploy.yml

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+name: Deploy
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - uses: pnpm/setup@v1
+        with:
+          version: 11
+          runtime: node@24
+          cache: true
+      - name: Build
+        run: pnpm build
+      - name: Deploy to Netlify
+        run: npx -y netlify-cli deploy --prod --dir=build
+        env:
+          NETLIFY_AUTH_TOKEN: ${{ secrets.NETLIFY_AUTH_TOKEN }}
+          NETLIFY_SITE_ID: ${{ secrets.NETLIFY_SITE_ID }}

.forgejo/workflows/pr.yml

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+name: PR Gate
+
+on:
+  pull_request:
+    branches:
+      - main
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.number || github.sha }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read # to fetch code (actions/checkout)
+
+jobs:
+  checks:
+    name: Checks
+    runs-on: ubuntu-24.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - uses: pnpm/setup@v1
+        with:
+          version: 11
+          runtime: node@24
+          cache: true
+      - name: Lint
+        run: pnpm lint
+      - name: Svelte Check
+        run: pnpm check
+      - name: Test
+        run: pnpm run test:unit
+      - name: Build
+        run: pnpm run build