## Thinking Path
<!-- 1-3 sentences: why this change, what alternative was considered. -->

## What Changed
<!-- Which Brain files? New / updated / superseded? -->

## Supersession Rule
<!-- For deletions or replacements: did old content get a `superseded_by:` link instead of being silently removed? See CLAUDE.md §1. -->
- [ ] No silent deletions — superseded content has frontmatter pointer or LRN reference
- [ ] Wiki-links to/from changed notes still valid

## Verification
- [ ] Frontmatter valid (title / type / tags / date / status)
- [ ] File under bootstrap-cap (12 KB) if it's a SessionStart-loaded root file
- [ ] No screenshots / large binaries in diff

## Risks
<!-- What might confuse Aria's recall after this change? -->

## Model Used
<!-- claude-opus-4-7, claude-sonnet-4-6, claude-haiku-4-5, manual, mixed. -->

## Checklist
- [ ] One logical change per PR
- [ ] No secrets in diff
- [ ] Commit author has real email (not `*.local` — see LRN-20260506-005)