docs: add Roo Code appendix to primitives matrix (#195)

[shixi-li]

Summary

Add a Roo Code appendix to docs/primitives-matrix.md using the final official
documentation snapshot and the extension's current archived status.

Changes

• New pattern or starter
• Doc / example improvement
• Tool change
• Story

The appendix:

• maps scheduling, skills, portable state, maker/checker separation, and MCP;
• distinguishes task-local todos/checkpoints from committed STATE.md;
• records the May 15, 2026 shutdown of the extension, Cloud, and Router;
• provides an attended, read-only week-one Daily Triage prompt with no auto-fix;
• adds an explicit L2+ human gate and fresh read-only checker; and
• documents the missing scheduler, support, and hard-isolation boundaries.

Capability links are pinned to the final official Roo Code documentation commit
so the claims remain reviewable after the hosted products and extension were
shut down.

Checklist

• Appendix is directly after Aider and near the other editor agents
• Scheduling, skills, state, maker/checker, and connectors/MCP are covered
• Week-one Daily Triage is report-only and does not edit repository state
• Honest gaps and the product lifecycle are explicit
• L2+ work requires a human gate and separate read-only checker
• No secrets, tokens, or internal URLs

Testing / Dogfood

• bash scripts/ci-validate-gates.sh
• bash scripts/ci-audit-gates.sh
• bash scripts/before-after-demo.sh
• node tools/loop-audit/dist/cli.js . --json — 100/100, L3
• git diff --check
• Verified every capability and lifecycle claim against official Roo Code
  documentation at commit a676c4173ae60348095efaebfd1292a9617622c0

Screenshots / Examples

Not applicable; this is a Markdown-only documentation change. The appendix
contains the copy-paste report-only prompt.

Closes #195

[github-actions]

Thanks @shixi-li for contributing a docs improvement — visible, reviewable PRs like this grow the reference for everyone.

What happens next

• Maintainer aims for same-day review on story, adopter, and scoped docs/example PRs (CONTRIBUTING.md).
• good first issue PRs: comment on the linked issue so we can assign and close on merge.

More ways to help

• Contributor quickstart + open issues
• Good first issue backlog

— loop-engineering maintainers

[cobusgreyling]

LGTM — Roo Code appendix is honest about sunset/archive status, report-only week-one prompt, clear maker/checker and gaps. Closes #195. CI green.