fix(models): allowlist routing for model-pinned Claude families (W1)

resolveModel lowercases input and strips one trailing [...] context marker.
Opus 4.7, Opus 4.8 and Sonnet 5 keep their pinned overlay only for the bare
ID, the bare ID plus an 8-digit date, and the bare ID plus -latest; any other
suffix (point releases such as claude-sonnet-5-5, claude-opus-4-7-1) falls to
the generic claude overlay. claude-opus-5-5 routes to claude explicitly (no new
overlay, no new ALL_MODEL_NAMES entry). Fable keeps its prefix match while
CLAUDE_FRONTIER_EVAL_MODEL is claude-fable-5-1, guarded by a test.

Tests: one test/model-overlays.test.ts case per shape in the plan, plus the
lowercase / [1m] marker / family-name cases and the Fable guard.

test/model-overlays.test.ts

@@ -10,6 +10,7 @@ import type { TemplateContext } from '../scripts/resolvers/types';
 import { HOST_PATHS } from '../scripts/resolvers/types';
 import { generateModelOverlay } from '../scripts/resolvers/model-overlay';
 import { resolveModel } from '../scripts/models';
+import { CLAUDE_FRONTIER_EVAL_MODEL } from '../lib/eval-model';
 import { readOverlay } from '../scripts/resolvers/model-overlay';
 import { generateCompletenessSection } from '../scripts/resolvers/preamble/generate-completeness-section';
 import { generateSetupCommand } from '../scripts/resolvers/utility';
@@ -368,3 +369,47 @@ describe('Sonnet 5 overlay — family nudges', () => {
   });
 });
 });
+
+describe('model-routing-claude', () => {
+  test.each([
+    ['claude-opus-4-7', 'opus-4-7'],
+    ['claude-opus-4-7-20260416', 'opus-4-7'],
+    ['claude-opus-4-7-latest', 'opus-4-7'],
+    ['claude-opus-4-7-1', 'claude'],
+    ['claude-opus-4-7-1-20260601', 'claude'],
+    ['claude-opus-4-8', 'opus-4-8'],
+    ['claude-opus-4-8-20260701', 'opus-4-8'],
+    ['claude-opus-4-8-latest', 'opus-4-8'],
+    ['claude-opus-4-8-1', 'claude'],
+    ['claude-sonnet-5', 'sonnet-5'],
+    ['claude-sonnet-5-20260115', 'sonnet-5'],
+    ['claude-sonnet-5-latest', 'sonnet-5'],
+    ['claude-sonnet-5-5', 'claude'],
+    ['claude-sonnet-5-5-20261001', 'claude'],
+    ['claude-sonnet-5-10', 'claude'],
+    ['claude-sonnet-5-latest-20260101', 'claude'],
+    ['claude-opus-5-5', 'claude'],
+    ['claude-fable-5', 'fable-5'],
+    ['claude-fable-5-1', 'fable-5'],
+  ])('%s routes to %s', (input, expected) => {
+    expect(resolveModel(input)).toBe(expected);
+  });
+
+  test('input is lowercased and one trailing [...] marker is stripped', () => {
+    expect(resolveModel('CLAUDE-SONNET-5')).toBe('sonnet-5');
+    expect(resolveModel('claude-sonnet-5[1m]')).toBe('sonnet-5');
+    expect(resolveModel('claude-opus-5-5[1m]')).toBe('claude');
+  });
+
+  test('family names force the pinned profile', () => {
+    expect(resolveModel('opus-4-7')).toBe('opus-4-7');
+    expect(resolveModel('opus-4-8')).toBe('opus-4-8');
+    expect(resolveModel('sonnet-5')).toBe('sonnet-5');
+  });
+
+  test('Fable prefix exception holds only while the frontier eval model is a Fable 5 point release', () => {
+    if (resolveModel('claude-fable-5-99') === 'fable-5') {
+      expect(CLAUDE_FRONTIER_EVAL_MODEL.startsWith('claude-fable-5-')).toBe(true);
+    }
+  });
+});