docs(developer-guide): address review on the pre-edit hook page

- The re-read step now sorts work.out by &sortpk after rebuilding it, matching
  getdata (which sorts before the hook runs and does not sort again), so the
  grid keeps the order the user first saw. The bullet records why.
- Adds a .pre-commit-config.yaml with the gitleaks hook pinned to v8.30.1, so
  staged content is scanned at commit time.

.pre-commit-config.yaml

@@ -0,0 +1,11 @@
+# Hooks for the pre-commit framework - https://pre-commit.com
+#
+# This repo carries no native git hooks, so this is the route for a secret scan
+# at commit time: install the framework once with `pre-commit install`, and the
+# scan then runs on every commit. The hook is pinned to an exact gitleaks
+# release tag.
+repos:
+  - repo: https://github.com/gitleaks/gitleaks
+    rev: v8.30.1
+    hooks:
+      - id: gitleaks