feat: add Debian package building to CI pipeline and local build

Support DEB packaging alongside RPM for Debian trixie (13/stable),
forky (14/testing), Ubuntu noble (24.04 LTS), and plucky (25.04).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitea/workflows/ci.yml

@@ -300,6 +300,9 @@ jobs:
       - name: Package RPM
         run: nfpm pkg --packager rpm --target dist/
 
+      - name: Package DEB
+        run: nfpm pkg --packager deb --target dist/
+
       - name: Upload RPM artifact
         uses: actions/upload-artifact@v3
         with:
@@ -307,6 +310,13 @@ jobs:
           path: dist/mcpctl-*.rpm
           retention-days: 7
 
+      - name: Upload DEB artifact
+        uses: actions/upload-artifact@v3
+        with:
+          name: deb-package
+          path: dist/mcpctl*.deb
+          retention-days: 7
+
   # ── Release pipeline (main branch push only) ──────────────
   # NOTE: Docker image builds + deploy happen via `bash fulldeploy.sh`
   # (not CI) because the runner containers lack the privileged access
@@ -363,3 +373,55 @@ jobs:
           # Link package to repo
           source scripts/link-package.sh
           link_package "rpm" "mcpctl"
+
+  publish-deb:
+    runs-on: ubuntu-latest
+    needs: [build]
+    if: github.ref == 'refs/heads/main' && github.event_name == 'push'
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Download DEB artifact
+        uses: actions/download-artifact@v3
+        with:
+          name: deb-package
+          path: dist/
+
+      - name: Publish DEB to Gitea
+        env:
+          GITEA_TOKEN: ${{ secrets.PACKAGES_TOKEN }}
+          GITEA_URL: http://${{ env.GITEA_REGISTRY }}
+          GITEA_OWNER: ${{ env.GITEA_OWNER }}
+          GITEA_REPO: mcpctl
+        run: |
+          DEB_FILE=$(ls dist/mcpctl*.deb | head -1)
+          DEB_VERSION=$(dpkg-deb --field "$DEB_FILE" Version)
+          echo "Publishing $DEB_FILE (version $DEB_VERSION)..."
+
+          # Publish to each supported distribution
+          # Debian: trixie (13/stable), forky (14/testing)
+          # Ubuntu: noble (24.04 LTS), plucky (25.04)
+          DISTRIBUTIONS="trixie forky noble plucky"
+
+          for DIST in $DISTRIBUTIONS; do
+            echo "  -> $DIST..."
+            HTTP_CODE=$(curl -s -o /dev/null -w "%{http_code}" \
+              -X PUT \
+              -H "Authorization: token ${GITEA_TOKEN}" \
+              --upload-file "$DEB_FILE" \
+              "${GITEA_URL}/api/packages/${GITEA_OWNER}/debian/pool/${DIST}/main/upload")
+
+            if [ "$HTTP_CODE" = "201" ] || [ "$HTTP_CODE" = "200" ]; then
+              echo "     Published to $DIST"
+            elif [ "$HTTP_CODE" = "409" ]; then
+              echo "     Already exists in $DIST (skipping)"
+            else
+              echo "     WARNING: Upload to $DIST returned HTTP $HTTP_CODE"
+            fi
+          done
+
+          echo "Published successfully!"
+
+          # Link package to repo
+          source scripts/link-package.sh
+          link_package "debian" "mcpctl"