[Planning] Triage Infra Repo Playbooks

## Epic: Triage Infra Repo Playbooks

### Description
Evaluate the extensibility of the current GitHub Event Processor vs GitHub Actions for repo-specific customization, and document per-repo triage playbooks capturing each language repo's unique assumptions around ownership, escalation, and workflows.

### Objective
Create the initial plan for the **Triage Infra Repo Playbooks** epic. This includes:
- Defining scope and success criteria
- Identifying key deliverables and milestones
- Mapping dependencies and risks
- Proposing an implementation approach
- Identifying stakeholders and owners