See ipfs/boxo#290

This PR follow the changes in the Pinner to make listing recursive and direct pins asynchronous, which in turns allow pin/ls to build and emit results without having to wait anything, or accumulate too much in memory.

Note: there is a tradeoff for pin/ls?type=all:
- keep the recursive pins in memory (which I chose)
- ask the pinner twice for the recursive pins, and limit memory usage

Also, follow the changes in the GC with similar benefit of not having to wait the full pin list. Add a test.
Also, follow the changes in pin.Verify.