fix(tests): fail a run whose selected case names no test in the file

A renamed or misspelled `only` path skipped every case, and the run was then
saved as passing. The harness now rejects unknown names, so the run is
recorded as an error with the names it could not find.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EHGBgHrtePpi7KMrEfy41R

Author: TheodoreSpeaks

apps/sim/sandbox-tasks/workflow-test.ts

@@ -488,6 +488,11 @@ const HARNESS = `
     async run() {
       const plan = this.collect();
       const { only } = await call('testPlan', {});
+      if (only) {
+        const known = new Set(plan.tests.map((t) => t.path.join(' > ')));
+        const unknown = only.filter((name) => !known.has(name));
+        if (unknown.length > 0) throw new Error('No test is named ' + unknown.map((name) => '"' + name + '"').join(', ') + ' in this file');
+      }
       const results = [];
       await runSuiteTree(root, only, results);
       return {