chore: #230 audit debt — lifecycle test gaps, doc corrections, guide parity, stale comments

[edheltzel]

Consolidated smaller follow-ups from the post-merge audit of #230 (reviewer report findings 4a/4c, 5, 7, 10, 11 + nits).

Tests

• RECALL_SKILL_NAMES ↔ agent-skills/ sync test (~10-line readdir-vs-array; uninstall test currently exercises 1 of 9 names)
• Restore the fix(install): stop legacy commands cleanup from deleting itself on case-insensitive filesystems #219 case-insensitivity regression pin (the -ef guard at lib/install-lib.sh:1190 survives but is no longer tested — tests/install/update.test.ts:216 replaced the old test)
• Contract test pinning disable-model-invocation: true in agent-skills/recall-dump/SKILL.md (agent-skills/AGENTS.md declares the gate; nothing asserts it)

Docs

• docs/architecture.md:21: skill canonicals shown at ~/.agents/Recall/claude/shared/skills/ — actual path is top-level ~/.agents/Recall/shared/skills/; also add skills/recall-*/ symlinks to the ~/.claude/ half of the tree
• FOR_PI.md: enumerate all 9 skills (currently 2 of 9; FOR_CLAUDE.md gained the full table in Migrate all /Recall:* slash commands to recall-* Agent Skills #230)
• ROLLBACK.txt/docs note: FILES_TO_BACKUP cannot restore command canonicals, so the rollback recipe can't undo the command-removal step (finding 7)

Stale comments/labels (one pass)

• update.sh:346 comment (+ mirrored wording in tests/install/update.test.ts:186-187); lib/install-lib.sh:36 and :45 comments; uninstall.sh:200 "(current)" label; empty .../claude/commands/ parent left behind (lib/install-lib.sh:1197)

Refs #230, #228.