[plan] Fix `create_pull_request` "context is not defined" error in safeoutputs MCP backend

[github-actions]

Objective

Fix the create_pull_request tool in the safeoutputs MCP backend that fails with context is not defined error.

Context

From audit discussion #18635 (2026-02-26→2026-02-27):

The Daily Documentation Updater successfully committed changes to branch docs/update-android-arm64-stem-commands-2026-02-27 but could not open a PR because create_pull_request failed 3 times with:

context is not defined

This is a backend error in the safeoutputs MCP server's create_pull_request handler.

Investigation Steps

1. Open actions/setup/js/safe_outputs_handlers.cjs (or equivalent handler file)
2. Find the create_pull_request handler function
3. Identify where context is referenced without being defined/passed
4. Check if context should be derived from the request parameters, environment, or a module import

Files to Investigate

• actions/setup/js/safe_outputs_handlers.cjs — handler implementation
• pkg/workflow/js/safe_outputs_handlers.cjs — if it exists
• Any file containing create_pull_request handler logic in actions/setup/js/

Approach

1. Locate the create_pull_request handler in the safeoutputs JS codebase
2. Identify the undefined context variable reference
3. Fix the reference (likely needs to be extracted from the handler's parameters or from a GitHub client initialization)
4. Run make fmt-cjs && make lint-cjs to validate
5. Run make agent-finish before committing

Acceptance Criteria

• create_pull_request handler no longer throws context is not defined
• The handler correctly creates a PR in the target repository
• make lint-cjs passes with no errors
• Existing safe-output tests still pass

Generated by Plan Command for issue #discussion #18635

• expires on Mar 1, 2026, 6:38 AM UTC

[pelikhan]

@copilot context is a global object that only exists in actions/github-script.

Add to shim.cjs