v1.92.70.0 test(free): build git fixtures once per file and copy them per test (GSTA-151 C) (#3586)

* test(free): build git fixtures once per file and copy them per test

test/helpers/git-fixture-template.ts builds a template once, copies it per test, rebinds every path-bearing file and fails on a leaked template path. Adopted by release-cut, train-backstop, restamp-mentions, pregate-user-policy and held-install-recovery; restamp-fixture's origin turns off auto-maintenance.

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* test(free): baseline the git fixture template regression test in the test-of-test ratchet

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* docs(changelog): unreleased entry for the git fixture templates (GSTA-151 C)

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Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "gstack",
-  "version": "1.92.69",
+  "version": "1.92.70",
   "description": "Garry's Stack — Claude Code skills + fast headless browser. One repo, one install, entire AI engineering workflow.",
   "license": "MIT",
   "type": "module",