Add sample code branch push step to PR verification agent (#137)

* Add sample code branch push step to PR verification agent

After verification passes, the agent now pushes the verification sample
to a dedicated branch (verification/pr-<N>) for future reference.

Changes:
- Added Step 5.5: Push Verification Sample to Branch
- Updated behavioral rules: clarify no source code changes, add branch isolation rule
- Updated success criteria to include branch pushing
- Updated Step 7: samples are now pushed, not deleted

* Update PR verification agent to push sample code and e2e tests to branch

- Add Step 5: Create E2E tests in test/e2e-azuremanaged/ for regression coverage
- Add Step 6: Push verification sample + e2e tests to verification/pr-<N> branch
- Remove duplicate Step 5.5 (old push logic) and consolidate into Step 6
- Update verification report format to include E2E test details and branch link
- Update hard constraints to allow creating verification artifacts and e2e tests
- Renumber steps for clean sequential flow (Steps 5-9)

* Remove e2e test creation from PR verification agent

The agent now only pushes verification samples to branch, without
creating e2e tests in test/e2e-azuremanaged/.

Author: YunchuWang

.github/agents/pr-verification.agent.md

@@ -1,4 +1,4 @@
----
+---
 name: pr-verification
 description: >-
   Autonomous PR verification agent that finds PRs labeled pending-verification,
@@ -304,7 +304,62 @@ If the verification **fails**, investigate:
 - Is the sample correct?
 - Retry up to 2 times before reporting failure.
 
-## Step 5: Post Verification to Linked Issue
+## Step 5: Push Verification Sample to Branch
+
+After verification passes, push the sample to a dedicated branch so it is
+preserved and can be reviewed.
+
+### Branch Creation
+
+Create a branch from the **PR's branch** (not from `main`) named:
+```
+verification/pr-<pr-number>
+```
+
+For example, for PR #123:
+```bash
+git checkout -b verification/pr-123
+```
+
+### Files to Commit
+
+Commit the following file to the branch:
+
+1. **Verification sample** — the standalone script created in Step 3.
+   Place it at: `examples/verification/pr-<pr-number>-<short-description>.ts`
+   (e.g., `examples/verification/pr-123-whenall-failfast.ts`)
+
+### Commit and Push
+
+```bash
+# Stage the verification sample
+git add examples/verification/
+
+# Commit with a descriptive message
+git commit -m "chore: add verification sample for PR #<pr-number>
+
+Verification sample: examples/verification/pr-<pr-number>-<description>.ts
+
+Generated by pr-verification-agent"
+
+# Push the branch
+git push origin verification/pr-<pr-number>
+```
+
+### Branch Naming Rules
+
+- Always use the prefix `verification/pr-`
+- Include only the PR number, not the issue number
+- Branch names must be lowercase with hyphens
+- If the branch already exists on the remote, skip pushing (idempotency)
+
+Check if the branch already exists before pushing:
+```bash
+git ls-remote --heads origin verification/pr-<pr-number>
+```
+If it exists, skip the push and note it in the verification report.
+
+## Step 6: Post Verification to Linked Issue
 
 Post a comment on the **linked GitHub issue** (not the PR) with the verification report.
 
@@ -334,6 +389,10 @@ Post a comment on the **linked GitHub issue** (not the PR) with the verification
 
 </details>
 
+### Sample Code Branch
+
+- **Branch:** `verification/pr-<pr-number>` ([view branch](https://github.com/microsoft/durabletask-js/tree/verification/pr-<pr-number>))
+
 ### Results
 
 | Check | Expected | Actual | Status |
@@ -353,14 +412,14 @@ Post a comment on the **linked GitHub issue** (not the PR) with the verification
 
 ### Conclusion
 
-<PASS: "All verification checks passed. The fix works as described in the PR.">
+<PASS: "All verification checks passed. The fix works as described in the PR. Verification sample pushed to `verification/pr-<pr-number>` branch.">
 <FAIL: "Verification failed. See details above. The fix may need additional work.">
 ```
 
 **Important:** The comment must start with `<!-- pr-verification-agent -->` (HTML comment)
 so the idempotency check in Step 1 can detect it.
 
-## Step 6: Update PR Labels
+## Step 7: Update PR Labels
 
 After posting the verification comment:
 
@@ -372,18 +431,26 @@ If verification **failed**, do NOT update labels. Instead:
    failed and needs manual review.
 2. Leave the `pending-verification` label in place.
 
-## Step 7: Clean Up
+## Step 8: Clean Up
 
-- Delete the temporary verification sample file (it's captured in the issue comment).
+- Do NOT delete the verification sample — it has been pushed to the
+  `verification/pr-<number>` branch.
 - Do NOT stop the DTS emulator (other tests or agents may be using it).
+- Switch back to `main` before processing the next PR:
+  ```bash
+  git checkout main
+  ```
 
 ## Behavioral Rules
 
 ### Hard Constraints
 
 - **Idempotent:** Never post duplicate verification comments. Always check first.
-- **No code changes:** This agent does NOT modify any source files in the repository.
-  It only creates temporary sample files, runs them, and posts results.
+- **Verification artifacts only:** This agent creates verification samples in
+  `examples/verification/`. It does NOT modify any existing SDK source files
+  in the repository.
+- **Push to verification branches only:** All artifacts are pushed to
+  `verification/pr-<number>` branches, never directly to `main` or the PR branch.
 - **No PR merges:** This agent does NOT merge or approve PRs. It only verifies.
 - **Never modify generated files** (`*_pb.js`, `*_pb.d.ts`, `*_grpc_pb.js`).
 - **Never modify CI/CD files** (`.github/workflows/`, `eng/`, `azure-pipelines.yml`).
@@ -419,5 +486,6 @@ A successful run means:
 - All `pending-verification` PRs were processed (or correctly skipped)
 - Verification samples accurately test the PR's fix scenario
 - Evidence is posted to the correct GitHub issue
+- Verification samples are pushed to `verification/pr-<N>` branches
 - Labels are updated correctly
 - Zero duplicate work