Add standardized Sourcegraph CI (build checks + code intel)

.github/workflows/sg-ci-go.yml

@@ -0,0 +1,50 @@
+name: SG CI - Go
+on:
+  push:
+  pull_request:
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: stable
+      - name: gofmt
+        run: |
+          out=$(gofmt -l .)
+          if [ -n "$out" ]; then echo "Unformatted files:"; echo "$out"; exit 1; fi
+      - name: go vet and build (per module)
+        run: |
+          set -e
+          mods=$(find . -name go.mod -not -path '*/vendor/*')
+          if [ -z "$mods" ]; then echo "no go.mod found; nothing to vet/build"; exit 0; fi
+          for mod in $mods; do
+            dir=$(dirname "$mod")
+            echo "=== $dir ==="
+            (cd "$dir" && go vet ./... && go build ./...)
+          done
+  code-intel:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: stable
+      - name: Generate SCIP index (gate)
+        uses: sourcegraph/scip-go-action@v2
+        with:
+          upload: false
+          recursive: true
+      - name: Upload SCIP index (best-effort)
+        continue-on-error: true
+        env:
+          SRC_ENDPOINT: https://demo.sourcegraph.com
+          SRC_ACCESS_TOKEN: ${{secrets.SRC_ACCESS_TOKEN}}
+        run: |
+          curl -sfL https://demo.sourcegraph.com/.api/src-cli/src_linux_amd64 -o /usr/local/bin/src
+          chmod +x /usr/local/bin/src
+          find . -name index.scip -print0 | while IFS= read -r -d '' f; do
+            echo "Uploading $f"
+            (cd "$(dirname "$f")" && src code-intel upload -file=index.scip -no-progress) || echo "upload failed for $f (non-blocking)"
+          done