merge: resolve version/changelog conflicts with main (v0.12.10.0)

Main shipped v0.12.10.0 (Codex filesystem boundary fix: prevents Codex
from wandering into skill definition files). Our branch keeps v0.13.0.0.
Both changelog entries preserved in order: 0.13.0.0 > 0.12.10.0 > 0.12.9.0.

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

CHANGELOG.md

@@ -1,5 +1,6 @@
 # Changelog
 
+<<<<<<< HEAD
 ## [0.13.0.0] - 2026-03-27 — Your Agent Can Design Now
 
 gstack can generate real UI mockups. Not ASCII art, not text descriptions of hex codes, real visual designs you can look at, compare, pick from, and iterate on. Run `/office-hours` on a UI idea and you'll get 3 visual concepts in Chrome with a comparison board where you pick your favorite, rate the others, and tell the agent what to change.
@@ -33,6 +34,16 @@ gstack can generate real UI mockups. Not ASCII art, not text descriptions of hex
 - Tests: `design/test/serve.test.ts` (11 tests), `design/test/gallery.test.ts` (7 tests)
 - Full design doc: `docs/designs/DESIGN_TOOLS_V1.md`
 
+## [0.12.10.0] - 2026-03-27 — Codex Filesystem Boundary
+
+Codex was wandering into `~/.claude/skills/` and following gstack's own instructions instead of reviewing your code. Now every codex prompt includes a boundary instruction that keeps it focused on the repository. Covers all 11 callsites across /codex, /autoplan, /review, /ship, /plan-eng-review, /plan-ceo-review, and /office-hours.
+
+### Fixed
+
+- **Codex stays in the repo.** All `codex exec` and `codex review` calls now prepend a filesystem boundary instruction telling Codex to ignore skill definition files. Prevents Codex from reading SKILL.md preamble scripts and wasting 8+ minutes on session tracking and upgrade checks.
+- **Rabbit-hole detection.** If Codex output contains signs it got distracted by skill files (`gstack-config`, `gstack-update-check`, `SKILL.md`, `skills/gstack`), the /codex skill now warns and suggests a retry.
+- **5 regression tests.** New test suite validates boundary text appears in all 7 codex-calling skills, the Filesystem Boundary section exists, the rabbit-hole detection rule exists, and autoplan uses cross-host-compatible path patterns.
+
 ## [0.12.9.0] - 2026-03-27 — Community PRs: Faster Install, Skill Namespacing, Uninstall
 
 Six community PRs landed in one batch. Install is faster, skills no longer collide with other tools, and you can cleanly uninstall gstack when needed.