feat: Pin golangci-lint version to v2.12.1 and update configuration comments for consistency

Signed-off-by: Alex Lovell-Troy <alex@lovelltroy.org>

Author: alexlovelltroy

.github/workflows/golangci-lint.yaml

@@ -28,6 +28,10 @@ jobs:
       - name: Run golangci-lint
         uses: golangci/golangci-lint-action@v6
         with:
-          version: latest
+          # Pinned to v2; `latest` resolves to the newest v1 in this action
+          # (1.64.x as of 2026-05), which can't read tests/.golangci.yml.
+          # When bumping, keep this in sync with the `version: "2"` declared
+          # in tests/.golangci.yml.
+          version: v2.12.1
           working-directory: tests
           args: --build-tags=integration

tests/.golangci.yml

@@ -3,7 +3,8 @@
 # SPDX-License-Identifier: MIT
 #
 # golangci-lint config for the integration test suite.
-# Format: golangci-lint v2.
+# Format: golangci-lint v2 (matches the binary pinned in
+# .github/workflows/golangci-lint.yaml — keep the two in sync).
 
 version: "2"