Add dead-lettering, TTL, and overflow handling to virtual queues

Normalized profile

What this task asks for

Add dead-letter routing, TTL expiry, and max-length overflow handling to the virtual transport layer. Persist queue properties in shared broker state and convert queue keyword arguments to and from `x-*` arguments. Resolve dead-letter exchanges, routing keys, and effective message TTL from queue attributes or arguments. Apply per-message or per-queue expiration and evict oldest messages when maximum queue length is exceeded. Skip and dead-letter expired messages during retrieval and expose remaining-TTL and drain operations. Route rejected, expired, and max-length messages through the configured DLX with cycle and hop limits. Maintain `x-death` and first-death headers while clearing expiration metadata on dead-lettered messages.