fix(hooks): correct the false deferral claim in check-regen-pending.mjs and .githooks/pre-commit

.githooks/pre-commit

@@ -6,12 +6,18 @@
 # exits before doing any work, which is every commit that did not just merge a
 # generator-owned artifact (#4675).
 #
-# One commit is exempt, and only one: the MERGE commit itself, which the
-# sanctioned landing sequence (`scripts/pm/os-regen-merge.sh`, step 3) commits
-# BEFORE regenerating, so that "what main brought" stays readable apart from
-# "what the change produces". That commit records a deferral instead of being
-# refused; the immediately following commit must discharge it, and
-# `.githooks/pre-push` refuses the push if none ever does (#8047).
+# One commit is exempt, and only one: a MERGE commit finished BY HAND, with
+# `MERGE_HEAD` present at commit time — a conflicted merge an operator
+# resolves and finishes with `git commit`. That commit records a deferral
+# instead of being refused; the immediately following commit must discharge
+# it, and `.githooks/pre-push` refuses the push if none ever does (#8047).
+#
+# The sanctioned landing sequence (`scripts/pm/os-regen-merge.sh`) does NOT
+# hit that exemption: its step 1 merge auto-commits with no hook run at all
+# (see below), so the marker is untouched going into step 3, whose commit is
+# an ORDINARY one this hook refuses on purpose — that refusal is the designed
+# collection point, "what main brought" read apart from "what the change
+# produces" by the fallback it prints, not a deferral.
 #
 # ⚠️ git does not run this hook for a merge it completes ITSELF — only for one
 # you finish with `git commit`. A clean auto-committed merge therefore lands

scripts/check-regen-pending.mjs

@@ -411,9 +411,11 @@ function main({ prePush = false } = {}) {
     console.error(
       `\nRegenerate ${owed}, \`git add\` them, and ${prePush ? 'commit the result before pushing' : 'commit again'}.\n`
         + '  This check clears itself the moment they are current — nothing to reset by hand.\n'
-        + '  Landing a merge? `bash scripts/pm/os-regen-merge.sh` runs the sanctioned sequence — it commits\n'
-        + '  the merge first (this hook records that as a deferral) and regeneration follows as its own\n'
-        + '  commit. Every artifact above also has a required gate on the PR.\n',
+        + '  Landing a merge? `bash scripts/pm/os-regen-merge.sh` runs the sanctioned sequence — its merge\n'
+        + '  auto-commits first with no hook run at all (git skips pre-commit for a merge it completes\n'
+        + '  itself), so THIS refusal, on the ordinary commit right after, is that sequence\'s designed\n'
+        + '  collection point — not a deferral. Regeneration follows as its own commit; every artifact\n'
+        + '  above also has a required gate on the PR.\n',
     );
     return 1;
   }