Add copilot prompt to fix PR CI failures

Author: trask

.github/prompts/fix-pr-ci-failures.md

@@ -0,0 +1,95 @@
+---
+mode: agent
+---
+
+# Fix PR CI failures
+
+Analyze the CI failures in the PR for the current branch and fix them, following the structured plan below.
+
+Each time this prompt is triggered, assume you are starting fresh from the beginning of the process.
+
+Do not stop a given execution until you have worked through all phases below.
+
+## Phase 0: Validate
+
+1. Verify we're not on a protected branch: `git branch --show-current` should not be `main`
+2. Check that the branch is up-to-date with remote: `git fetch && git status` - exit and warn if behind
+3. Get the current branch name using `git branch --show-current`
+4. Find the PR for this branch using `gh pr list --head <branch-name> --json number,title` and extract the PR number
+5. Use `gh pr view <pr-number> --json statusCheckRollup` to get the list of all failed CI jobs
+6. Check if there are actually CI failures to fix - if all jobs passed, exit early
+
+## Phase 1: Gather Information
+
+**Phase 1 is for gathering information ONLY. Do NOT analyze failures or look at any code during this phase.**
+**Your only goal in Phase 1 is to collect: job names, job IDs, log files, and failed task names.**
+
+1. Get repository info: `gh repo view --json owner,name`
+2. For unique job type that failed
+    - **Important**: Ignore duplicate jobs that only differ by parameters inside of parenthesis. For example:
+        - In `abc / def (x, y, z)`, the job is `abc / def` while x, y, and z are parameters
+    - **Strategy**: Download logs for 1-2 representative jobs first to identify patterns (e.g., one "build" job, one "test0" job)
+    - Compilation failures typically repeat across all jobs, so you don't need every log file
+  - Retrieve logs for selected representative jobs:
+    - Get the job ID from the failed run by examining the PR status checks JSON
+    - Download logs using: `cd /tmp && gh auth token | xargs -I {} curl -sSfL -H "Authorization: token {}" -o <job-name>.log "https://api.github.com/repos/<owner>/<repo>/actions/jobs/<job-id>/logs"`
+    - Example: `cd /tmp && gh auth token | xargs -I {} curl -sSfL -H "Authorization: token {}" -o test0-java8-indy-false.log "https://api.github.com/repos/open-telemetry/opentelemetry-java-instrumentation/actions/jobs/53713949850/logs"`
+    - The GitHub API responds with an HTTP 302 redirect to blob storage; `-L` (already included) ensures the download follows the redirect and saves the final log contents.
+    - Find all gradle tasks that failed:
+        - Search for failed tasks: `grep "Task.*FAILED" /tmp/<job-name>.log`
+        - Look for test failures: `grep "FAILED" /tmp/<job-name>.log | grep -E "(Test|test)"`
+        - Example output: `> Task :instrumentation:cassandra:cassandra-4.0:javaagent:test FAILED`
+    - Extract error context:
+        - For compilation errors: `grep -B 5 -A 20 "error:" /tmp/<job-name>.log`
+        - For task failures: `grep -B 2 -A 15 "Task.*FAILED" /tmp/<job-name>.log`
+
+## Phase 2: Create CI-PLAN.md
+
+**ONLY:** Create the CI-PLAN.md file in the repository root with the following structure:
+
+```markdown
+# CI Failure Analysis Plan
+
+## Failed Jobs Summary
+- Job 1: <job-name> (job ID: <id>)
+- Job 2: <job-name> (job ID: <id>)
+...
+
+## Unique Failed Gradle Tasks
+
+- [ ] Task: <gradle-task-path>
+  - Seen in: <job-name-1>, <job-name-2>, ...
+  - Log files: /tmp/<file1>.log, /tmp/<file2>.log
+  
+- [ ] Task: <gradle-task-path>
+  - Seen in: <job-name-1>, <job-name-2>, ...
+  - Log files: /tmp/<file1>.log, /tmp/<file2>.log
+
+## Notes
+[Any patterns or observations about the failures]
+```
+
+## Phase 3: Fix Issues
+
+**Important**: Do not commit CI-PLAN.md - it's only for tracking work during the session
+
+- Work through the CI-PLAN.md, checking items off as you complete them
+- For each failed task:
+  - Analyze the failure
+  - Implement the fix
+  - **Test locally before committing**:
+    - For compilation errors: `./gradlew <failed-task-path>`
+    - For test failures: `./gradlew <failed-test-task>`
+    - Verify the fix resolves the issue
+  - Update the checkbox in CI-PLAN.md
+  - Commit each logical fix as a separate commit
+    - Reminder: do not commit CI-PLAN.md
+- Do not git push in this phase
+
+## Phase 4: Validate and Push
+
+- Once all fixes are committed, push the changes: `git push` (or `git push -f` if needed)
+- Provide a summary of:
+  - What failures were found
+  - What fixes were applied
+  - Which commits were created