feat: external + in-process plugins (4 transports incl. native dylib)

.github/workflows/heph.yml

@@ -169,24 +169,32 @@ jobs:
         env:
           CARGO_TARGET_DIR: "./target"
           BIN_NAME: "heph_${{ matrix.os }}_${{ matrix.arch }}"
+          PLUGIN_GO_NAME: "heph-plugin-go_${{ matrix.os }}_${{ matrix.arch }}"
           HEPH_BUILD_VERSION: "${{needs.gen.outputs.version}}"
         run: |
           echo "bin_name=$BIN_NAME" >> $GITHUB_OUTPUT
+          echo "plugin_go_name=$PLUGIN_GO_NAME" >> $GITHUB_OUTPUT
+          # Build the CLI and the out-of-process go plugin together (one cargo
+          # invocation shares the compile). The go plugin is published so a
+          # workspace can launch it via `bin: { url: ... }` without building it.
+          OUT="$CARGO_TARGET_DIR/${{ matrix.target }}/release"
           # FUSE (default feature) on Linux is pure-Rust (no libfuse link), so
           # zigbuild cross-compiles cleanly. On macOS it links libfuse via the
           # devenv macfuse-stubs; zig mangles the nix `-L` path under its SDK
           # syslibroot and fails to find `-lfuse`, so the (native arm64) macOS
           # runner uses plain `cargo build` — no cross needed there.
           if [ "${{ matrix.os }}" = "darwin" ]; then
-            cargo build --release --locked --target ${{ matrix.target }} --bin heph
+            cargo build --release --locked --target ${{ matrix.target }} -p heph --bin heph -p plugin-go --bin heph-plugin-go
             # The nix toolchain hard-links libiconv against its /nix/store path,
             # which is absent on user machines (dyld aborts at launch). Rewrite
             # those load commands to the OS /usr/lib copies.
-            bash scripts/macos-portable.sh $CARGO_TARGET_DIR/${{ matrix.target }}/release/heph
+            bash scripts/macos-portable.sh "$OUT/heph"
+            bash scripts/macos-portable.sh "$OUT/heph-plugin-go"
           else
-            cargo zigbuild --release --locked --target ${{ matrix.target }} --bin heph
+            cargo zigbuild --release --locked --target ${{ matrix.target }} -p heph --bin heph -p plugin-go --bin heph-plugin-go
           fi
-          cp $CARGO_TARGET_DIR/${{ matrix.target }}/release/heph $BIN_NAME
+          cp "$OUT/heph" $BIN_NAME
+          cp "$OUT/heph-plugin-go" $PLUGIN_GO_NAME
 
       - name: sccache stats
         if: always()
@@ -208,6 +216,12 @@ jobs:
           name: ${{steps.build.outputs.bin_name}}
           path: ${{steps.build.outputs.bin_name}}
 
+      - name: Upload go plugin artifact
+        uses: actions/upload-artifact@v6
+        with:
+          name: ${{steps.build.outputs.plugin_go_name}}
+          path: ${{steps.build.outputs.plugin_go_name}}
+
   upload_artifacts:
     name: Upload artifacts
     needs: [gen, build]
@@ -220,7 +234,9 @@ jobs:
       - name: Download all artifacts
         uses: actions/download-artifact@v7
         with:
-          pattern: "heph_*"
+          # Matches the CLI (`heph_<os>_<arch>`) and the go plugin
+          # (`heph-plugin-go_<os>_<arch>`); excludes the `repo` source artifact.
+          pattern: "heph*"
           path: dist
           merge-multiple: true