misc(p2p/peerTracker): peerTracker improvement

Last week we discussed with @Wondertan ways to improve the peer tracker:
* https://github.com/celestiaorg/go-header/pull/159 introduces adding peers who are currently syncing back to the queue to request them one more time. We should add a backoff for these peers;
* move scoring to the Connection Manager under a specific tag;
* remove limiting for 100 tracked peers in the peer tracker;
* check peer support for the protocol. We should migrate from Connect event to Identify.

Start by reading pull request 159 and the peer tracker, Connection Manager, Connect event, and Identify flows mentioned in the issue. Map the four proposed changes and confirm their interactions before implementing them. Done means peers have backoff, scoring uses a Connection Manager tag, the 100-peer limit is removed, and protocol support is checked through Identify.

Written by the indexing model from the issue text.