[update] pipeline to track last update.

Author: vmarcella

.github/workflows/coverage.yml

@@ -110,9 +110,14 @@ jobs:
           CHANGED_FILES: ${{ steps.changed.outputs.files }}
           RUN_ID: ${{ github.run_id }}
           REPO: ${{ github.repository }}
+          COMMIT_SHA: ${{ github.event.pull_request.head.sha }}
         run: |
           # Base URL for GitHub Pages coverage (from main branch)
           PAGES_BASE="https://lambda-sh.github.io/lambda/coverage"
+          # Get current timestamp in UTC
+          TIMESTAMP=$(date -u +"%Y-%m-%d %H:%M:%S UTC")
+          # Short commit SHA for display
+          SHORT_SHA="${COMMIT_SHA:0:7}"
 
           # Build the comment body
           {
@@ -169,6 +174,8 @@ jobs:
             echo ""
             echo "---"
             echo "*Generated by [cargo-llvm-cov](https://github.com/taiki-e/cargo-llvm-cov) · [Latest main coverage](${PAGES_BASE})*"
+            echo ""
+            echo "<sub>Last updated: ${TIMESTAMP} · Commit: [\`${SHORT_SHA}\`](https://github.com/${REPO}/commit/${COMMIT_SHA})</sub>"
           } > comment_body.md
 
           # Store as output (handle multiline)