Add publish workflow for Gitea Go Package Registry

Publishes the module to Gitea Package Registry on tag push (v*).
Runs vet and tests before publishing to prevent broken releases.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitea/workflows/publish.yml

@@ -0,0 +1,39 @@
+name: Publish
+
+on:
+  push:
+    tags: ["v*"]
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-go@v5
+        with:
+          go-version: "1.24"
+
+      - name: Vet
+        run: go vet ./...
+
+      - name: Test
+        run: go test -race -count=1 ./...
+
+      - name: Publish to Gitea Package Registry
+        run: |
+          VERSION=${GITHUB_REF#refs/tags/}
+          MODULE=$(go list -m)
+          go mod download
+          GOFLAGS=-mod=mod go install golang.org/x/mod/zip@latest
+          zip -r module.zip . -x '.git/*' '.gitea/*'
+
+          # Gitea Go Package Registry API
+          curl -s -f \
+            -X PUT \
+            -H "Authorization: token ${{ secrets.PUBLISH_TOKEN }}" \
+            -H "Content-Type: application/zip" \
+            --data-binary @module.zip \
+            "${{ github.server_url }}/api/packages/pkg/go/upload?module=${MODULE}&version=${VERSION}"
+        env:
+          PUBLISH_TOKEN: ${{ secrets.PUBLISH_TOKEN }}