chore: bump golangci-lint-action v7 → v9 (Node 24) (#4936)

golangci-lint-action v8+ requires golangci-lint v2 (this repo
already pins v2.11.4). v9 runs on Node 24, eliminating the
upcoming Node 20 deprecation warning.

Made-with: Cursor

Author: bryanbeverly

.github/workflows/lint.yml

@@ -20,7 +20,7 @@ jobs:
         with:
           go-version: "1.25"
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@v7
+        uses: golangci/golangci-lint-action@v9
         with:
           # NOTE: Version and args must match scripts/lint.sh
           version: v2.11.4