test(benchmarks): add C#/ASP.NET and TypeScript tasks

Six tasks with hidden checks: ASP.NET validation and 404 handling, C#
cancellation, and TypeScript overlap, deep merge, and debounce fixes, checked
with dotnet run and node --test.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/benchmarks/tasks/19-ts-debounce-arguments/hidden/check.test.ts

@@ -0,0 +1,18 @@
+import { test, mock } from 'node:test';
+import assert from 'node:assert/strict';
+import { debounce } from '../src/debounce.ts';
+
+test('trailing call uses the latest arguments', () => {
+  mock.timers.enable({ apis: ['setTimeout'] });
+  const calls: number[][] = [];
+  const run = debounce((value: number) => calls.push([value]), 50);
+  run(1); run(2); run(3);
+  mock.timers.tick(49);
+  assert.deepEqual(calls, []);
+  mock.timers.tick(1);
+  assert.deepEqual(calls, [[3]]);
+  run(4);
+  mock.timers.tick(50);
+  assert.deepEqual(calls, [[3], [4]]);
+  mock.timers.reset();
+});

scripts/benchmarks/tasks/19-ts-debounce-arguments/repo/package.json

@@ -0,0 +1,5 @@
+{
+  "name": "timing",
+  "type": "module",
+  "private": true
+}

scripts/benchmarks/tasks/19-ts-debounce-arguments/repo/src/debounce.ts

@@ -0,0 +1,15 @@
+export function debounce<T extends unknown[]>(fn: (...args: T) => void, wait: number): (...args: T) => void {
+  let timer: ReturnType<typeof setTimeout> | undefined;
+  let pending: T | undefined;
+  return (...args: T) => {
+    if (pending === undefined) {
+      pending = args;
+    }
+    clearTimeout(timer);
+    timer = setTimeout(() => {
+      const call = pending as T;
+      pending = undefined;
+      fn(...call);
+    }, wait);
+  };
+}

scripts/benchmarks/tasks/19-ts-debounce-arguments/task.json

@@ -0,0 +1,13 @@
+{
+  "prompt": "debounce() calls the wrapped function with the arguments of the first call in a burst instead of the last one. Fix it so the trailing call uses the latest arguments.",
+  "check": [
+    "node",
+    "--experimental-strip-types",
+    "--no-warnings",
+    "--test",
+    "bench_hidden/check.test.ts"
+  ],
+  "workflow": {
+    "kind": "TypeScript change"
+  }
+}