CI: Add artifact packaging and upload to build workflow

- Install to custom prefix for clean packaging
- Create versioned tarball with xz compression
- Generate SHA256 checksum
- Upload artifacts with 30-day retention

.gitea/workflows/build.yml

@@ -85,7 +85,9 @@ jobs:
           exit $EXITCODE
 
       - name: Install
-        run: pixi run install-release
+        run: |
+          # Install to a custom prefix for packaging
+          pixi run cmake --install build/release --prefix build/release/install
 
       - name: Run Python CLI tests
         timeout-minutes: 10
@@ -94,3 +96,33 @@ jobs:
       - name: Run GUI tests (headless)
         timeout-minutes: 10
         run: pixi run timeout 300 xvfb-run -a build/release/bin/FreeCAD -t 0 || true
+
+      - name: Package build artifacts
+        shell: bash
+        run: |
+          # Create a distributable tarball from the installed build
+          ARTIFACT_NAME="kindred-create-$(git describe --tags --always)-linux-x86_64"
+          echo "Creating artifact: ${ARTIFACT_NAME}"
+
+          # The install step puts files in build/release/install
+          cd build/release
+          if [ -d "install" ]; then
+            mv install "${ARTIFACT_NAME}"
+            tar -cJf "${ARTIFACT_NAME}.tar.xz" "${ARTIFACT_NAME}"
+            sha256sum "${ARTIFACT_NAME}.tar.xz" > "${ARTIFACT_NAME}.tar.xz.sha256"
+            echo "ARTIFACT_NAME=${ARTIFACT_NAME}" >> $GITHUB_ENV
+            ls -lh "${ARTIFACT_NAME}.tar.xz"
+          else
+            echo "ERROR: install directory not found"
+            ls -la
+            exit 1
+          fi
+
+      - name: Upload build artifact
+        uses: https://code.forgejo.org/actions/upload-artifact@v3
+        with:
+          name: ${{ env.ARTIFACT_NAME }}
+          path: |
+            build/release/*.tar.xz
+            build/release/*.sha256
+          retention-days: 30