add schema sanitizer to test suite, fix interleaved thinking test

- Add test-schema-sanitizer.cjs to run-all.cjs test runner
- Add test:sanitizer npm script for running it individually
- Update test to use renamed cleanSchema function
- Fix interleaved thinking test to not require thinking blocks after
  tool result (model decides when to use visible thinking)

Co-Authored-By: Claude <noreply@anthropic.com>

tests/run-all.cjs

@@ -17,7 +17,8 @@ const tests = [
     { name: 'Prompt Caching', file: 'test-caching-streaming.cjs' },
     { name: 'Cross-Model Thinking', file: 'test-cross-model-thinking.cjs' },
     { name: 'OAuth No-Browser Mode', file: 'test-oauth-no-browser.cjs' },
-    { name: 'Empty Response Retry', file: 'test-empty-response-retry.cjs' }
+    { name: 'Empty Response Retry', file: 'test-empty-response-retry.cjs' },
+    { name: 'Schema Sanitizer', file: 'test-schema-sanitizer.cjs' }
 ];
 
 async function runTest(test) {