feat: added local separator implementation

src/util/localSeparatorTiming.ts

@@ -0,0 +1,52 @@
+export class LocalSeparatorTimingCollector {
+  private readonly label: string;
+  private readonly sections = new Map<string, { totalMs: number; count: number }>();
+  private readonly startedAt = performance.now();
+
+  constructor(label = 'timing') {
+    this.label = label;
+  }
+
+  private track(name: string, durationMs: number): void {
+    const section = this.sections.get(name) ?? { totalMs: 0, count: 0 };
+    section.totalMs += durationMs;
+    section.count += 1;
+    this.sections.set(name, section);
+  }
+
+  public async measureAsync<T>(name: string, fn: () => Promise<T>): Promise<T> {
+    const started = performance.now();
+    try {
+      return await fn();
+    } finally {
+      this.track(name, performance.now() - started);
+    }
+  }
+
+  public measureSync<T>(name: string, fn: () => T): T {
+    const started = performance.now();
+    try {
+      return fn();
+    } finally {
+      this.track(name, performance.now() - started);
+    }
+  }
+
+  public getSummary(extra: Record<string, unknown> = {}): Record<string, unknown> {
+    const sections: Record<string, { totalMs: number; count: number; averageMs: number }> = {};
+    for (const [name, section] of this.sections.entries()) {
+      sections[name] = {
+        totalMs: Number(section.totalMs.toFixed(2)),
+        count: section.count,
+        averageMs: Number((section.totalMs / Math.max(section.count, 1)).toFixed(2)),
+      };
+    }
+
+    return {
+      label: this.label,
+      totalMs: Number((performance.now() - this.startedAt).toFixed(2)),
+      sections,
+      ...extra,
+    };
+  }
+}