ci: migrate PDF release pipeline from Woodpecker to Gitea Actions (host/fish)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitea/workflows/release.yml

@@ -0,0 +1,31 @@
+name: Release PDFs
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  pdfs:
+    # Host executor (runs on kasse as gitea-runner) using fish; pandoc/typst/jq are on the host.
+    # Replaces the retired Woodpecker `local` backend.
+    runs-on: fish
+    defaults:
+      run:
+        shell: fish {0}
+    steps:
+      - name: Checkout code
+        uses: https://gitea.com/actions/checkout@v6
+
+      - name: Render markdown to PDF and attach to the release
+        env:
+          TOKEN: ${{ github.token }}
+        run: |
+          mkdir -p dist
+          curl -sLo icon.svg https://klingenbergbygg.no/icon-normalized.svg
+          for md in (find . -name "*.md" ! -path "./.git/*")
+            pandoc -f gfm+tex_math_dollars -t pdf -o "dist/$(basename $md .md).pdf" --pdf-engine=typst --template=stil.typ $md
+          end
+          set REL_ID (curl --silent --fail --header "Authorization: token $TOKEN" "$GITHUB_SERVER_URL/api/v1/repos/$GITHUB_REPOSITORY/releases/tags/$GITHUB_REF_NAME" | jq -r '.id')
+          for pdf in (find dist -name '*.pdf')
+            curl --silent --show-error --fail --header "Authorization: token $TOKEN" --form "attachment=@$pdf" "$GITHUB_SERVER_URL/api/v1/repos/$GITHUB_REPOSITORY/releases/$REL_ID/assets?name=$(basename $pdf)"
+          end