feat(scanners): model/effort routing becomes a lever, not a 25th dimension (C4)

New GAP finding CA-GAP-028: authored subagents exist and not one of them names
`model:` or `effort:`, so every delegated task runs on the main conversation's
model (`model` defaults to `inherit`). Cites BP-MODEL-001/002, landed in C1.
`whats-active` and `manifest` now carry `model`/`effort` per agent.

Shipped as a conditional LEVER rather than a 25th dimension, and the choice was
made by measurement: as a t3 dimension the agent-less marketplace-medium fixture
would count it vacuously-present, moving the denominators 41->42 and utilization
44->45 — which flips `segment` "Developing"->"Competent" in the frozen v5.0.0
posture baseline, a field strip-retired-gap.mjs does not mask. A lever never
enters those denominators. The general rule is now an invariant in CLAUDE.md.

One check across both axes, not one per axis: it fires only when neither is used
anywhere, so a deliberate everything-on-one-model policy stays silent. Cost is
recall, chosen for precision.

Found by dogfooding, fixed red-first: `model: inherit` is the documented default
spelled out, so it must not count as routing — otherwise a config opts out of the
opportunity without changing anything real.

Two pre-existing defects surfaced and closed on the way:
- The humanizer guard asserted TRANSLATIONS.GAP.static EQUALS the dimension
  titles, which forbade humanizing any lever — all three existing levers fell
  through to the generic "feature opportunity" default, wrong for a budget lever.
  Guard now requires coverage of every emittable title, seen red against those
  three before the entries were written.
- Two hand-written copies of the lever list (finding-codes guard, humanizer
  guard) merged into one exported LEVERS registry carrying code AND title.
- suppression-validation pinned CA-GAP-028 as an unoccupied number; C4 claimed
  it. Fixed structurally with a derived first-free id, not by picking a new
  literal — same class as #60's "bump this again".

Suite 1596/0. Frozen v5.0.0 snapshots untouched.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Pq3nye21RVYk4pZLeT8pGz

tests/scanners/manifest.test.mjs

@@ -123,7 +123,7 @@ describe('buildManifest — load-pattern accounting (unit)', () => {
     ],
     agents: [
       { name: 'a1', source: 'project', pluginName: null, estimatedTokens: 5,
-        ...deriveLoadPattern('agent') },
+        model: 'sonnet', effort: null, ...deriveLoadPattern('agent') },
     ],
     outputStyles: [
       { name: 's1', source: 'project', pluginName: null, estimatedTokens: 7,
@@ -165,6 +165,14 @@ describe('buildManifest — load-pattern accounting (unit)', () => {
     assert.equal(byName('output-style', 's1').loadPattern, 'always');
   });
 
+  // C4. withLoadPattern copies the explicit row object plus three load-pattern
+  // fields and nothing else, so routing fields do NOT ride along from the
+  // enumeration — they have to be named in the row.
+  it('C4: carries model and effort on agent rows', () => {
+    assert.equal(byName('agent', 'a1').model, 'sonnet');
+    assert.equal(byName('agent', 'a1').effort, null);
+  });
+
   it('tags MCP servers always and hooks external', () => {
     assert.equal(byName('mcp-server', 'm1').loadPattern, 'always');
     assert.equal(byName('hook', 'PreToolUse:Edit').loadPattern, 'external');