enhancing auto label feature (Stanzin7#219)

* Add auto-label backfill mode

* Use plain issue labels for auto-labeling

* Enhance PR auto-labeling with keyword rules

Author: sapnilbiswas

.github/workflows/auto-label.yml

@@ -154,6 +154,124 @@ jobs:
           configuration-path: .github/labeler.yml
           sync-labels: true
 
+  pr-keyword-labels:
+    name: Label PRs From Title And Body
+    if: github.event_name == 'pull_request_target'
+    needs: ensure-labels
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Apply labels from PR keywords
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const pullRequest = context.payload.pull_request;
+            const text = `${pullRequest.title || ""}\n${pullRequest.body || ""}`.toLowerCase();
+            const managedLabels = [
+              "bug",
+              "feature",
+              "documentation",
+              "question",
+              "security",
+              "kind: bug",
+              "kind: feature",
+              "kind: documentation",
+              "kind: question",
+              "kind: security",
+            ];
+            const rules = [
+              {
+                label: "security",
+                patterns: [
+                  /\bsecurity\b/,
+                  /\bvulnerability\b/,
+                  /\bxss\b/,
+                  /\bcsrf\b/,
+                  /\binjection\b/,
+                  /\bmalware\b/,
+                  /\bcve\b/,
+                ],
+              },
+              {
+                label: "bug",
+                patterns: [
+                  /\bbug\b/,
+                  /\bbugfix\b/,
+                  /\bfix\b/,
+                  /\bfixes\b/,
+                  /\bfixed\b/,
+                  /\bregression\b/,
+                  /\berror\b/,
+                  /\bcrash\b/,
+                  /\bbroken\b/,
+                  /\bfailing\b/,
+                  /\bfailed\b/,
+                ],
+              },
+              {
+                label: "documentation",
+                patterns: [
+                  /\bdocs?\b/,
+                  /\breadme\b/,
+                  /\bdocumentation\b/,
+                  /\bguide\b/,
+                ],
+              },
+              {
+                label: "feature",
+                patterns: [
+                  /\bfeature\b/,
+                  /\benhancement\b/,
+                  /\brequest\b/,
+                  /\bidea\b/,
+                  /\bproposal\b/,
+                  /\badd\b/,
+                  /\bintroduce\b/,
+                  /\bimplement\b/,
+                ],
+              },
+              {
+                label: "question",
+                patterns: [
+                  /\bquestion\b/,
+                  /\bhow do i\b/,
+                  /\bhow to\b/,
+                  /\bhelp\b/,
+                ],
+              },
+            ];
+
+            const expected = rules
+              .filter((rule) => rule.patterns.some((pattern) => pattern.test(text)))
+              .map((rule) => rule.label);
+            const existing = (pullRequest.labels || [])
+              .map((label) => typeof label === "string" ? label : label.name)
+              .filter(Boolean);
+            const toRemove = existing.filter((label) => managedLabels.includes(label) && !expected.includes(label));
+            const toAdd = expected.filter((label) => !existing.includes(label));
+
+            for (const label of toRemove) {
+              await github.rest.issues.removeLabel({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: pullRequest.number,
+                name: label,
+              });
+              core.info(`PR #${pullRequest.number}: removed ${label}`);
+            }
+
+            if (toAdd.length > 0) {
+              await github.rest.issues.addLabels({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: pullRequest.number,
+                labels: toAdd,
+              });
+              core.notice(`PR #${pullRequest.number}: added ${toAdd.join(", ")}`);
+            } else if (toRemove.length === 0) {
+              core.info(`PR #${pullRequest.number}: no keyword label changes needed`);
+            }
+
   issue-keyword-labels:
     name: Label Issues
     if: github.event_name == 'issues'