chore: bump version and changelog (v0.18.1.0)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -1,5 +1,19 @@
 # Changelog
 
+## [0.18.1.0] - 2026-04-17
+
+### Fixed
+- **`/ship` stops skipping `/document-release` ~80% of the time.** The old Step 8.5 told Claude to `cat` a 2500-line external skill file *after* the PR URL was already output, at which point the model had 500-1,750 lines of intermediate tool output in context and was at its least intelligent. Now `/ship` dispatches `/document-release` as a subagent that runs in a fresh context window, *before* creating the PR, so the `## Documentation` section gets baked into the initial PR body instead of a create-then-re-edit dance. The result: documentation actually syncs on every ship.
+
+### Changed
+- **`/ship`'s 4 heaviest sub-workflows now run in isolated subagent contexts.** Coverage audit (Step 7), plan completion audit (Step 8), Greptile triage (Step 10), and documentation sync (Step 18) each dispatch a subagent that gets a fresh context window. The parent only sees the conclusion (structured JSON), not the intermediate file reads. This is the pattern Anthropic's "Using Claude Code: Session Management and 1M Context" blog post recommends for fighting context rot: "Will I need this tool output again, or just the conclusion? If just the conclusion, use a subagent."
+- **`/ship` step numbers are clean integers 1-20 instead of fractional (`3.47`, `8.5`, `8.75`).** Fractional step numbers signaled "optional appendix" to the model and contributed to late-stage steps getting skipped. Clean integers feel mandatory. Resolver sub-steps that are genuinely nested (Plan Verification 8.1, Scope Drift 8.2, Review Army 9.1/9.2, Cross-review dedup 9.3) are preserved.
+- **`/ship` now prints "You are NOT done" after push.** Breaks the natural stopping point where the model was treating a pushed branch as mission-accomplished and skipping doc sync + PR creation.
+
+### For contributors
+- New regression guards in `test/skill-validation.test.ts` prevent drift back to fractional step numbers and catch cross-contamination between `/ship` and `/review` resolver conditionals.
+- Ship template restructure: old Step 8.5 (post-PR doc sync with `cat` delegation) replaced by new Step 18 (pre-PR subagent dispatch that invokes full `/document-release` skill with its CHANGELOG clobber protections, doc exclusions, risky-change gates, and race-safe PR body editing). Codex caught that the original plan's reimplementation dropped those protections; this version reuses the real `/document-release`.
+
 ## [0.18.0.1] - 2026-04-16
 
 ### Fixed

VERSION

@@ -1 +1 @@
-0.18.0.1
+0.18.1.0

package.json

@@ -1,6 +1,6 @@
 {
   "name": "gstack",
-  "version": "0.18.0.1",
+  "version": "0.18.1.0",
   "description": "Garry's Stack — Claude Code skills + fast headless browser. One repo, one install, entire AI engineering workflow.",
   "license": "MIT",
   "type": "module",