feat(onboarding): Semantic onboarding PR (#25666)

lib/workers/repository/onboarding/pr/index.spec.ts

@@ -77,6 +77,23 @@ describe('workers/repository/onboarding/pr/index', () => {
       expect(platform.createPr).toHaveBeenCalledTimes(1);
     });
 
+    it('creates semantic PR', async () => {
+      await ensureOnboardingPr(
+        {
+          ...config,
+          semanticCommitType: undefined, // should default to "chore"
+          semanticCommits: 'enabled',
+        },
+        packageFiles,
+        branches,
+      );
+      expect(platform.createPr).toHaveBeenCalledWith(
+        expect.objectContaining({
+          prTitle: 'chore: Configure Renovate',
+        }),
+      );
+    });
+
     it('creates PR with labels', async () => {
       await ensureOnboardingPr(
         {

lib/workers/repository/onboarding/pr/index.ts

@@ -173,10 +173,16 @@ If you need any further assistance then you can also [request help here](${
       logger.info('DRY-RUN: Would create onboarding PR');
     } else {
       // TODO #22198
+      const prTitle =
+        config.semanticCommits === 'enabled'
+          ? `${config.semanticCommitType ?? 'chore'}: ${
+              config.onboardingPrTitle
+            }`
+          : config.onboardingPrTitle!;
       const pr = await platform.createPr({
         sourceBranch: config.onboardingBranch!,
         targetBranch: config.defaultBranch!,
-        prTitle: config.onboardingPrTitle!,
+        prTitle,
         prBody,
         labels,
         platformOptions: getPlatformPrOptions({