fix(process): reject pending promises when clearing command lane

clearCommandLane() was truncating the queue array without calling
resolve/reject on pending entries, causing never-settling promises
and memory leaks when upstream callers await enqueueCommandInLane().

Splice entries and reject each before clearing so callers can handle
the cancellation gracefully.

src/process/command-queue.ts

@@ -162,7 +162,10 @@ export function clearCommandLane(lane: string = CommandLane.Main) {
     return 0;
   }
   const removed = state.queue.length;
-  state.queue.length = 0;
+  const pending = state.queue.splice(0);
+  for (const entry of pending) {
+    entry.reject(new Error("Command lane cleared"));
+  }
   return removed;
 }