Make REST API accept both PeerIDs and chain addresses

[NumberFour8]

Description

There's been an ongoing discussion whether the API inputs should be unified to accept only peer IDs or chain addresses.
Going only with the former or latter means a backward incompatible change to the REST API.

The resolution is actually quite simple and even backwards compatible: since peer IDs and chain addresses have clearly distinct text representation, the API can accept both and do the conversion internally.

Relevant issues

• New or updated API routes accepting Eth Address insidead of PeerId #6078

Definition of DONE

• channels APIs updated
• tickets APIs updated
• node APIs updated