chore(release): v0.19.0

Version bump via changesets.

packages/engine/CHANGELOG.md

@@ -1,5 +1,18 @@
 # @fusion/engine
 
+## 0.19.0
+
+### Patch Changes
+
+- 54f2832: Restrict merger staging to squash + fix-agent files; refuse to commit unrelated working-tree changes
+
+  Replaces the blanket `git add -A` in `commitOrAmendMergeWithFixes` with an explicit allowlist: only files that were squash-staged or explicitly modified by the in-merge verification fix agent are staged. Any other dirty files in the working tree are left untouched and a warning is logged naming each excluded path. Fixes a production bug where ~13 unrelated user-edited files were bundled into a task's squash commit.
+
+  Hardened by code review: replaced all shell-interpolated `git add` calls in `commitOrAmendMergeWithFixes` and the conflict-resolution helpers (`resolveWithOurs`, `resolveWithTheirs`, `resolveTrivialWhitespace`) with `execFile` array form to eliminate path-injection surface; adopted `git -z` NUL-delimited output for all dirty-file path queries in both `snapshotDirtyFiles` and `commitOrAmendMergeWithFixes` so paths with embedded spaces round-trip correctly; truncated long allowlist debug log lines to at most 20 entries.
+
+  - @fusion/core@0.19.0
+  - @fusion/pi-claude-cli@0.19.0
+
 ## 0.18.1
 
 ### Patch Changes

packages/engine/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@fusion/engine",
-  "version": "0.18.1",
+  "version": "0.19.0",
   "license": "MIT",
   "description": "Fusion engine: executor, merger, scheduler, and automation runtime for the Fusion AI coding agent.",
   "homepage": "https://github.com/Runfusion/Fusion#readme",