docs: complete README skill lists — 34 → 36 skills, both blocks aligned (v0.16.2.1)

[ignsm]

Summary

Pure documentation fix. Brings the README's skill lists and skill table in line with what ./setup actually installs into ~/.claude/skills/. Zero code changes, zero runtime effect.

The README has two skill-list strings users paste into their CLAUDE.md when they set up gstack in a new project:

1. Install command block (line 49) — the blurb Claude Code is supposed to insert into CLAUDE.md during fresh install.
2. "## gstack" CLAUDE.md example block (line 396) — the copy-paste example in the troubleshooting section.

Over time these drifted apart, AND both had fallen behind the actual ./setup output. Before this PR:

• Install block (34 skills): had /connect-chrome, /plan-devex-review, /devex-review. Missing /pair-agent, /health, /checkpoint.
• CLAUDE.md example (32 skills): had /open-gstack-browser, /pair-agent. Missing /plan-devex-review, /devex-review, /health, /checkpoint.

After this PR both blocks list the same 36 skills in the same order, matching what ./setup registers on a clean install.

On top of that, /health and /checkpoint also get two new rows in the big sprint skill table — both have been working skills for a while (health/SKILL.md, checkpoint/SKILL.md), but the README didn't mention them anywhere, so new users had no way to discover them.

Bisection

Three clean commits, each independently revertable:

1. 6ef5696b — docs: complete and align README skill lists (36 skills, both blocks identical)

   • Adds /pair-agent to the install block.
   • Adds /plan-devex-review, /devex-review to the CLAUDE.md example block.
   • Replaces legacy /connect-chrome with canonical /open-gstack-browser.
   • Adds /health and /checkpoint to both blocks.
   • Verified via extracted-list diff: both blocks produce identical sorted sets.

2. 63753d3f — docs: add /health and /checkpoint rows to README skill table

   • Two new rows in the big sprint skill table. /health after /benchmark (both measurement tools). /checkpoint after /learn (both session/state tools).
   • Specialist roles chosen to avoid adjacency collisions: /health → "Quality Engineer" (next to "Performance Engineer" for /benchmark), /checkpoint → "Session Bookmark" (avoids collision with /learn's "Memory").

3. 4d11ef72 — chore: bump version and changelog (v0.16.2.1) (VERSION + CHANGELOG.md)

What's NOT in this PR

The Node server bundle build fix is deliberately out of scope. That fix is already in flight:

• fix(browse): use --outdir for Windows node server build #924 by @garrett-fox — switches to --outdir + mv. Keeps @ngrok/ngrok bundled so Windows Node users get tunneling out of the box. Arguably the better approach because it preserves the "it just works" property for the target platform.
• fix(browse): externalize @ngrok/ngrok in node server build #947 by @exabird — marks @ngrok/ngrok as --external. Simpler but shifts the install burden to Windows Node users.

Either approach fixes the ./setup build error. I didn't want to triple-post the fix, so this PR stays README-only.

Voice calibration

Both new skill table entries match the existing table voice:

• Lead with what the user can DO, not implementation details.
• Include the concrete trigger phrase in quotes so readers know how to activate.
• Avoid AI vocabulary (no "leverage", "robust", "comprehensive").
• Pick a specialist role that doesn't collide with adjacent table entries.

/health → Quality Engineer — "Wraps your project's type checker, linter, test runner, dead code detector, and shell linter into one weighted 0-10 composite score. Tracks trends over time so you see whether the codebase is improving or rotting. Say 'how healthy is the codebase' and you get one number plus a per-tool breakdown."

/checkpoint → Session Bookmark — "Save and resume working state mid-sprint. Captures git state, decisions made, and what's left to do so you can pick up exactly where you left off, even across Conductor workspace handoffs or after a long break. Say 'where was I' or 'pick up where I left off' and it reads the latest checkpoint."

Test plan

• grep "^## \[" CHANGELOG.md shows contiguous version sequence (0.16.2.1, 0.16.2.0, 0.16.1.0, 0.16.0.0, 0.15.16.0, 0.15.15.1, ...)
• Both README skill-list blocks contain the same 36 skills in the same order (verified via extracted-list diff: install block line 49 and CLAUDE.md example block lines 396-401 produce identical sorted sets)
• All 5 added skills appear in both blocks: /pair-agent, /plan-devex-review, /devex-review, /health, /checkpoint
• Legacy /connect-chrome removed from the install block (still exists as a symlink alias at checkpoint-chrome → open-gstack-browser so existing installs keep working)
• Big skill table has new rows for /health (after /benchmark) and /checkpoint (after /learn)
• Both new skills resolve to real SKILL.md files on disk: checkpoint/SKILL.md, health/SKILL.md
• Both new skills get linked by ./setup into ~/.claude/skills/checkpoint/SKILL.md and ~/.claude/skills/health/SKILL.md (verified on the upgrade session that surfaced this gap)

🤖 Generated with Claude Code