Node/P2P: Add protected peers list

[bruce-riley]

This PR adds the ability to specify a set of P2P peer IDs that should be added to the protected list.

Guardian

This is done for the guardian with something like this:

--protectedPeers 12D3KooWE4dmZwxhfjCKHLUqSaww96Cf7kmq1ZuKmzPz3MrJgZxp,12D3KooWMkxuNh1abxCRjsfNZ9D2C8ZgcsQ4xxbXBuuqdxVRbasu \
--protectedPeers 12D3KooWCW3LGUtkCVkHZmVSZHzL3C4WRKWfqAiJPz1NR7dT9Bxh,12D3KooWJXA6goBCiWM8ucjzc4jVUBSqL9Rri6UpjHbkMPErz5zK \
--ccqProtectedPeers 12D3KooWE4dmZwxhfjCKHLUqSaww96Cf7kmq1ZuKmzPz3MrJgZxp,12D3KooWMkxuNh1abxCRjsfNZ9D2C8ZgcsQ4xxbXBuuqdxVRbasu \
--ccqProtectedPeers  12D3KooWCW3LGUtkCVkHZmVSZHzL3C4WRKWfqAiJPz1NR7dT9Bxh,12D3KooWJXA6goBCiWM8ucjzc4jVUBSqL9Rri6UpjHbkMPErz5zK \

Note that there can be multiple instances of the same parameter, and each instance may contain either a single peer ID or a comma separated list of them.

Spy and CCQ proxy Server

The Spy and the CCQ proxy Server also support the --protectedPeers parameter.

[evan-gray]

Concur this parameter follows the pattern of something like https://docs.anza.xyz/operations/setup-an-rpc-node. My understanding is that this would optionally inform the connection manager to maintain connections to these peer IDs should the number of connections grow past the high watermark. It is akin to the automatic code that does this based on guardian heartbeats here.