feat(installer): npx installer CLI (@garrytan/gstack) — interactive wizard + team init

installer/.gitignore

@@ -0,0 +1,4 @@
+node_modules/
+dist/
+*.tgz
+.DS_Store

installer/.npmignore

@@ -0,0 +1,5 @@
+src/
+tsconfig.json
+node_modules/
+*.tgz
+.DS_Store

installer/PUBLISHING.md

@@ -0,0 +1,57 @@
+# Publishing `@garrytan/gstack`
+
+This installer is designed to be published to the `@garrytan` npm scope. That scope is owned by [@garrytan](https://github.com/garrytan), so merging this PR by itself does not put it on npm — Garry (or a maintainer with scope access) needs to run `npm publish`.
+
+## Steps for Garry / scope owner
+
+```bash
+cd installer
+npm install
+npm run build
+npm publish --access public
+```
+
+Users can then run:
+
+```bash
+npx @garrytan/gstack
+```
+
+## Testing before publish (non-scope-owners)
+
+If you want to verify `npx @garrytan/gstack` end-to-end without waiting for a publish, you can temporarily publish under your own npm scope:
+
+1. Change `"name"` in `installer/package.json` to your scope — e.g. `"@your-handle/gstack"`.
+2. `npm login`
+3. `npm publish --access public`
+4. `npx @your-handle/gstack`
+
+Revert the `name` field before merging the PR. **Do not** commit a scope change — the upstream PR should land with `@garrytan/gstack`.
+
+## Version bumps
+
+The installer has its own `version` independent of the main `gstack` `VERSION` file. Bump `installer/package.json` when:
+
+- New command or flag added
+- Existing command behavior changes
+- A bug fix ships
+
+Follow semver: `0.x.y` while the API is still settling, `1.0.0` when the command surface is stable.
+
+## What the installer does at runtime
+
+The installer is a thin wrapper — it clones `https://github.com/garrytan/gstack.git` into `~/.claude/skills/gstack` and shells out to that repo's `./setup` script. So publishing a new installer version **does not** ship a new gstack — users always get the latest `main` branch of the main repo at install time.
+
+This means the installer rarely needs to change. The main reasons would be:
+
+- Host registry expands (new agent supported by gstack)
+- `./setup` learns a new flag the installer wants to surface
+- Bug in the installer itself
+
+## CI (future)
+
+Not wired yet. A reasonable path:
+
+- `installer/` gets its own workflow at `.github/workflows/installer-ci.yml`
+- Runs `npm install`, `npm run build`, `npm pack` on PRs
+- On release tag `installer-v*`, runs `npm publish`

installer/README.md

@@ -0,0 +1,83 @@
+# `@garrytan/gstack` — installer CLI
+
+Interactive installer for [gstack](https://github.com/garrytan/gstack), Garry Tan's Claude Code skill pack and workflow tooling.
+
+## Usage
+
+```bash
+# Zero-friction: interactive wizard
+npx @garrytan/gstack
+
+# Scripted: verb-based subcommands
+npx @garrytan/gstack install --host claude,codex
+npx @garrytan/gstack install --local           # vendored (deprecated — prefer team mode)
+npx @garrytan/gstack init --tier required
+npx @garrytan/gstack upgrade
+npx @garrytan/gstack uninstall --project --yes
+npx @garrytan/gstack uninstall --local --yes    # remove vendored project install
+npx @garrytan/gstack doctor
+npx @garrytan/gstack status
+npx @garrytan/gstack list
+npx @garrytan/gstack disable /qa
+npx @garrytan/gstack enable /qa
+```
+
+Works with `npx`, `bunx`, and `pnpm dlx`.
+
+## What it does
+
+**`install`** — clones gstack into `~/.claude/skills/gstack`, builds the browse/design binaries via `bun`, registers with your chosen AI hosts (Claude Code, Codex, Factory Droid, OpenCode, Kiro), and inserts a `<!-- gstack:begin -->` / `<!-- gstack:end -->` block into `~/.claude/CLAUDE.md` documenting the available skills.
+
+**`install --local`** — vendored mode: installs gstack into `<cwd>/.claude/skills/gstack` instead of the home directory. Everything stays inside the project. **Deprecated upstream** in favor of team mode (`init`) because vendoring means no cross-project auto-update and ~100MB duplicated per project. Exposed here because `./setup --local` still supports it. Claude Code only (other hosts skipped).
+
+**`init`** — runs inside a git repo. Installs globally if needed, enables team mode (the SessionStart auto-update hook), runs `gstack-team-init <tier>` to bootstrap the repo, and stages/commits the changes. Teammates get gstack automatically on their next session.
+
+**`uninstall`** — removes the install and walks every host's skills directory (`~/.claude/skills`, `~/.codex/skills`, `~/.factory/skills`, `~/.config/opencode/skills`, `~/.kiro/skills`) removing any symlink or directory whose `SKILL.md` points into the gstack install. Cleans the CLAUDE.md block and scrubs the PreToolUse hook from project `settings.json`. `~/.gstack/` (session state) is preserved.
+
+**`upgrade`** — `git fetch` + hard reset to `origin/main` in `~/.claude/skills/gstack`, then re-runs `./setup --host auto` to rebuild and re-link.
+
+**`doctor`** — checks git, bun, install state, binary freshness, skill count, and per-host registration. Exit code 1 if any check fails.
+
+**`status`** — one-screen summary: version, install path, team mode, auto-upgrade, skill prefix mode, per-host registration, per-project disabled-skills list.
+
+**`list`** — enumerates installed skills with descriptions parsed from each `SKILL.md` frontmatter.
+
+**`enable <skill>` / `disable <skill>`** — toggle skills per-project via `.claude/settings.local.json`'s `disabledSkills` array. Names can be `qa`, `/qa`, or `gstack-qa` — all normalize to the same entry.
+
+## Requirements
+
+- Node.js 18+ (for the installer itself)
+- [bun](https://bun.sh/) 1.0+ (for building gstack binaries)
+- git
+- bash (Windows: Git Bash or WSL)
+
+## Philosophy
+
+The installer is a thin wrapper around gstack's existing [`./setup`](https://github.com/garrytan/gstack/blob/main/setup) bash script — no logic is duplicated. This keeps the installer small, auditable, and guaranteed to stay in sync with upstream. If `setup` learns a new flag, the installer picks it up by exposing a new option.
+
+## Development
+
+```bash
+cd installer
+npm install
+npm run build        # compile TS to dist/
+npm start -- --help  # run the built CLI
+
+# Watch mode
+npm run dev
+
+# Smoke test locally
+npm link
+gstack --help
+```
+
+To test without publishing:
+
+```bash
+# From anywhere, use the local checkout:
+npx /absolute/path/to/gstack/installer install
+```
+
+## License
+
+MIT — same as gstack.

installer/package.json

@@ -0,0 +1,55 @@
+{
+  "name": "@garrytan/gstack",
+  "version": "0.1.0",
+  "description": "Interactive installer for gstack — Garry Tan's Claude Code skills, hosts, and workflow tooling.",
+  "license": "MIT",
+  "type": "module",
+  "bin": {
+    "gstack": "./dist/cli.js"
+  },
+  "files": [
+    "dist",
+    "README.md",
+    "PUBLISHING.md"
+  ],
+  "engines": {
+    "node": ">=18"
+  },
+  "scripts": {
+    "build": "tsc",
+    "prepublishOnly": "npm run build",
+    "dev": "tsc --watch",
+    "start": "node dist/cli.js",
+    "clean": "rm -rf dist",
+    "test": "bun test test/",
+    "test:unit": "bun test test/unit/",
+    "test:integration": "bun run build && bun test test/integration/",
+    "pretest": "bun run build"
+  },
+  "keywords": [
+    "gstack",
+    "claude-code",
+    "skills",
+    "installer",
+    "cli",
+    "ai-agents"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/garrytan/gstack.git",
+    "directory": "installer"
+  },
+  "homepage": "https://github.com/garrytan/gstack#readme",
+  "bugs": {
+    "url": "https://github.com/garrytan/gstack/issues"
+  },
+  "dependencies": {
+    "@clack/prompts": "^0.7.0",
+    "picocolors": "^1.0.1"
+  },
+  "devDependencies": {
+    "@types/bun": "^1.3.13",
+    "@types/node": "^20.11.0",
+    "typescript": "^5.4.0"
+  }
+}