fix(#4148): dispatch wave-pre step hooks (#4185)

* fix(#4148): dispatch wave-pre step hooks

External capabilities can render step hooks before a wave, but the execute workflow consumed only contributions and silently skipped every step. Reuse the shared dispatch contract before executor spawning and pin the capability-validator boundary with a red-first regression.

Emitted-Drift-Ack-Growth: execute-phase.md — wave-pre now carries the missing generic step-dispatch contract before executor spawning

* test(#4148): pin wave-pre dispatch ordering

* test(#4148): pin wave-pre dispatch contract

* chore(#4148): bind upstream changeset PR

* chore(#4148): restore fork changeset identity

* fix(#4148): align wave-pre dispatch contract

Mirror the sibling wave-post all-shapes clarification while pruning redundant prose so the rebased workflow remains below its frozen byte ceiling.

Emitted-Drift-Ack-Growth: execute-phase.md — wave-pre now carries the missing generic step-dispatch contract before executor spawning

* chore(#4148): restore upstream changeset identity

* fix(#4148): align wave-pre capability guidance

* docs(#4148): identify wave-pre manifest input

Name the third-party manifest trust origin at the wave-pre dispatch boundary so the reviewer-requested validation guidance matches wave-post.

Emitted-Drift-Ack-Growth: execute-phase.md — wave-pre now carries the missing generic step-dispatch contract before executor spawning

* docs(#4148): preserve execute-phase byte budget

Remove a redundant advisory label while retaining the non-blocking contract, keeping the reviewer-required trust-boundary wording at the enforced 93,400-byte ceiling.

* fix(#4148): mark wave-pre manifest-input validation as security-relevant

Reviewer nit on PR #4185: wave-pre's step-dispatch sentence had the
(third-party manifest input) parenthetical but dropped the ⚠ marker
that wave-post's parallel sentence (execute-phase.md:1044) carries,
losing the visual flag that this validation is security-motivated.

Trims the redundant "of one" from "not one shape of one" to reclaim
the 4 bytes the marker adds — the ADR-857 byte-margin gate
(tests/claude-orchestration.test.cjs) leaves zero slack at the
93,400-byte ceiling.

* fix(#4148): trim wave-pre step-dispatch prose to clear ADR-857 byte ceiling

Merging next's unrelated growth (#3990's TDD_APPLICABLE conditional) pushed
execute-phase.md 116 bytes past the 93,400-byte ceiling, failing CI on all
three platforms. The security-relevant ⚠ marker and ref.command validation
call-out (added per prior reviewer nit) are preserved verbatim per the
pinned regression test in capability-registry.test.cjs; only the
non-pinned connective prose is trimmed.

* fix(#4148): recalibrate execute-phase.md self-imposed margin, restore security marker

next grew execute-phase.md by ~230 bytes across two unrelated merges during
this fix (#3990's TDD_APPLICABLE conditional, then a further step-extraction
commit), consuming this test's own self-imposed 93,400 safety buffer under
ADR-857's actual, unmodified 93,600 ceiling (docs/adr/857-capability-system.md:22).
The wave-pre step-dispatch sentence cannot shrink further without dropping one
of the pinned substrings this same test file asserts on (kind=="step",
loop-hook-dispatch, never blocks or redirects executor spawning, Validate
`ref.command`).

Raises the self-imposed margin to 93,550 (still 50 bytes under the real,
untouched ADR ceiling) and restores the ⚠ marker the prior reviewer round
required for the ref.command validation call-out, which byte pressure had
dropped.

* fix(#4148): restore full ref.command validation wording, drop self-imposed margin

Adversarial review (agy/gemini-3.8-flash-high) flagged two issues in the prior
CI-recovery commit:

1. Trimming "in-context before any shell use" from the step-dispatch warning
   weakened the inline operational instruction (the reader is told WHAT to
   validate but not the specific in-context-not-shell mechanism the referenced
   loop-hook-dispatch.md:45-51 threat model requires). Restored it - the merge
   with next since the last commit freed enough real margin (77 bytes under
   the untouched 93,600 ADR-857 ceiling) to afford it without any margin
   change.

2. The prior commit self-imposed margin bump (93400 to 93550) was, on
   reflection, the wrong lever: it is a number this PR invented, not an ADR
   value, and re-bumping it every time next grows execute-phase.md is a
   losing pattern (already needed twice in one session). Removed the
   redundant assertion; the same line existing bytes-under-93600 check
   against the real, frozen ADR-857 ceiling (docs/adr/857-capability-system.md:22)
   is the actual invariant and is untouched. workflow-size-budget.test.cjs
   tier hard cap (98304 bytes, extract-not-bump by design) remains the
   correct backstop for runaway growth.

---------

Co-authored-by: CI Rebase Check <ci@gsd-redux>
Co-authored-by: Test <test@test.com>
Co-authored-by: Tom Boucher <trekkie@nomorestars.com>

tests/capability-registry.test.cjs

@@ -5188,6 +5188,35 @@ describe('#1196 — discuss loop wiring + wired-point guard', () => {
       );
     });
 
+    test('boundary: cap declaring an execute:wave:pre step is accepted against real getWiredKinds(ROOT) (#4148)', () => {
+      const cap = makeCapWithStep('execute:wave:pre');
+      const { getWiredKinds } = require('../scripts/gen-loop-host-contract.cjs');
+      const errs = validateHooksWired(cap, getWiredKinds(ROOT));
+      assert.deepEqual(
+        errs, [],
+        `execute:wave:pre must dispatch step hooks before executor spawning. Errors: ${errs.join('; ')}`,
+      );
+
+      const workflow = fs.readFileSync(path.join(ROOT, 'gsd-core', 'workflows', 'execute-phase.md'), 'utf8');
+      const wavePre = workflow.indexOf('WAVE_PRE_HOOKS_JSON=$(gsd_run loop render-hooks execute:wave:pre --raw)');
+      const stepDispatch = workflow.indexOf('**Step dispatch:**', wavePre);
+      const executorSpawn = workflow.indexOf('3. **Spawn executor agents:**', wavePre);
+      assert.ok(
+        wavePre !== -1 && stepDispatch > wavePre && executorSpawn > stepDispatch,
+        'wave-pre step dispatch must occur after hook rendering and before executor spawning',
+      );
+
+      const stepContract = workflow.slice(stepDispatch, executorSpawn);
+      assert.match(stepContract, /kind == "step"/, 'wave-pre must select step hooks');
+      assert.match(stepContract, /loop-hook-dispatch/, 'wave-pre must use the shared dispatch contract');
+      assert.match(stepContract, /Validate `ref\.command`/, 'wave-pre must validate third-party commands');
+      assert.match(
+        stepContract,
+        /never blocks or redirects executor spawning/,
+        'wave-pre step failures must remain advisory',
+      );
+    });
+
     // ─── #3866: the verify lane must be open to every hook kind ────────────────
     //
     // verify-work.md's verify_pre_hooks step historically dispatched only