Allow the issues event in the observed-events policy before it is switched on #629

🤖 Generated by the Agentic Engineer (interactive Claude Code session)

Problem

The policy that limits which events may start a workflow, workflow-execution-policies/allow-observed-events.json, allows eight events and not issues. It is not switched on yet. devantler-tech/monorepo#4293 adds a monorepo workflow that starts on issues: labeled: it emails the maintainer at once when an ask is marked urgent. Once the policy is switched on, that workflow would stop starting, and urgent asks would wait for the weekly digest instead.

Proposed direction

Add issues to allowed_events before the policy moves to active, and update the README's count and table.

Acceptance criteria

• allow-observed-events.json allows issues, and the README describes nine events.
• The policy is applied, and its read-back matches.

Size

S. Part of #202.