[codex] add Go wrapper for C ABI

.github/workflows/ci.yml

@@ -94,6 +94,43 @@ jobs:
       - name: cargo clippy -p ordvec-ffi
         run: cargo clippy -p ordvec-ffi --all-targets -- -D warnings
 
+  # ----------------------------------------------------------------------
+  # Repo-local Go wrapper over the C ABI. Build the release static library
+  # first because the cgo wrapper links the source-tree archive directly.
+  # ----------------------------------------------------------------------
+  go-wrapper:
+    name: go wrapper (cgo)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          egress-policy: audit
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+      - uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8 # stable (2026-03-27)
+        with:
+          toolchain: stable
+      - uses: Swatinem/rust-cache@e18b497796c12c097a38f9edb9d0641fb99eee32 # v2
+      - name: cargo build -p ordvec-ffi --release
+        run: cargo build -p ordvec-ffi --release
+      - name: go test
+        working-directory: ordvec-go
+        env:
+          GOCACHE: ${{ runner.temp }}/go-build
+        run: go test -count=1 ./...
+      - name: go test -race
+        working-directory: ordvec-go
+        env:
+          GOCACHE: ${{ runner.temp }}/go-build
+        run: go test -race -count=1 ./...
+      - name: go test (cgocheck2)
+        working-directory: ordvec-go
+        env:
+          GOEXPERIMENT: cgocheck2
+          GOCACHE: ${{ runner.temp }}/go-build-cgocheck2
+        run: go test -count=1 ./...
+
   # ----------------------------------------------------------------------
   # Test matrix across the three GitHub-hosted OSes. Covers the default
   # surface, the experimental feature, the no-default-features build, and a

ordvec-go/README.md

@@ -0,0 +1,21 @@
+# ordvec-go
+
+Thin cgo wrapper over the local `ordvec-ffi` C ABI.
+
+Build the Rust library before running Go tests or linking a Go program:
+
+```sh
+cargo build -p ordvec-ffi --release
+cd ordvec-go
+go test ./...
+go test -race ./...
+GOEXPERIMENT=cgocheck2 go test ./...
+```
+
+`Index.Close` should be called explicitly. A finalizer is installed as a safety
+net, but it is not a resource-management strategy.
+
+Search with `nil` options or `nil` `SearchOptions.Candidates` performs a full
+search. An empty, non-nil `Candidates` slice is treated as an explicit empty
+subset and returns a typed `StatusBadArgument`, matching the C ABI v1
+pointer/count contract.

ordvec-go/go.mod

@@ -0,0 +1,4 @@
+module github.com/Fieldnote-Echo/ordvec/ordvec-go
+
+go 1.22
+