merge: incorporate origin/main into community-mode branch

Conflicts resolved:
- VERSION: keep 0.13.0.0 (branch > main's 0.12.12.0)
- package.json: same version resolution
- CHANGELOG.md: keep both entries — 0.13.0.0 on top, then 0.12.12.0/11.0/10.0
- scripts/gen-skill-docs.ts: keep resolvers-based architecture, drop main's
  inline Codex helper duplicates (already in scripts/resolvers/codex-helpers.ts)

Main brought in: security audit compliance (conditional telemetry, credential
cleanup, dead code removal), skill prefix choice, Codex filesystem boundary,
audit regression tests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

README.md

@@ -265,6 +265,10 @@ Data is stored in [Supabase](https://supabase.com) (open source Firebase alterna
 
 **Stale install?** Run `/gstack-upgrade` — or set `auto_upgrade: true` in `~/.gstack/config.yaml`
 
+**Want shorter commands?** `cd ~/.claude/skills/gstack && ./setup --no-prefix` — switches from `/gstack-qa` to `/qa`. Your choice is remembered for future upgrades.
+
+**Want namespaced commands?** `cd ~/.claude/skills/gstack && ./setup --prefix` — switches from `/qa` to `/gstack-qa`. Useful if you run other skill packs alongside gstack.
+
 **Codex says "Skipped loading skill(s) due to invalid SKILL.md"?** Your Codex skill descriptions are stale. Fix: `cd ~/.codex/skills/gstack && git pull && ./setup --host codex` — or for repo-local installs: `cd "$(readlink -f .agents/skills/gstack)" && git pull && ./setup --host codex`
 
 **Windows users:** gstack works on Windows 11 via Git Bash or WSL. Node.js is required in addition to Bun — Bun has a known bug with Playwright's pipe transport on Windows ([bun#4253](https://github.com/oven-sh/bun/issues/4253)). The browse server automatically falls back to Node.js. Make sure both `bun` and `node` are on your PATH.