… queue processing

generateUUID() was calling itself instead of crypto.randomUUID(), causing
a stack overflow whenever a package install was attempted from the missing
resources popup.

The queue start endpoint also had a race condition where concurrent
fire-and-forget requests would stomp on the shared running_task global,
causing an AttributeError crash when multiple nodes were installed at once.
Added an asyncio lock so only one handler drains the queue at a time.