feat(skills): route performance-slo-planner backlog through shared backlog-templates handoff

## Summary

Follow-up from the #2420 review (F3, @WilliamBerryiii). Route the reliability backlog through the shared `backlog-templates` handoff for parity with the sibling planners.

## Proposed changes

- Emit the backlog via the shared `backlog-templates` handoff (paired ADO + GitHub items, IDs, priorities, disclaimer).
- Reshape backlog items into the backlog-templates body (Implementation / Acceptance Criteria, priority, depends-on, and the `slo_id` each item protects).
- Add `runbook` and `operational-script` work-item types, which a reliability plan most needs.

## Context

Deferred from #2420 to keep that PR focused; this expands scope.

## Acceptance criteria

- Backlog output uses the backlog-templates handoff shape with `slo_id` linkage.
- `runbook` and `operational-script` work-item types are available.
- `npm run validate:skills` and `npm run lint:frontmatter` pass; plugins regenerated.

Start with the #2420 review and the sibling planners to compare their backlog-templates handoff. Run npm run validate:skills and npm run lint:frontmatter before changes, then inspect the skill and plugin generation flow. Done means the output has paired ADO and GitHub items with IDs, priorities, disclaimers, implementation and acceptance sections, depends-on links, slo_id values, and the two new work-item types; both checks pass and plugins are regenerated.

Written by the indexing model from the issue text.