Comet currently doesn't export many of its errors, which hinders programmatic use (i.e. by consensus engine developers). The only alternative for them is to detect specific errors by their string representations, which is prone to breakage even in patch releases of our software.

We should, package by package, ensure that all possible errors returned by publicly exported methods are defined programmatically (example) and publicly exported too.

Per package (check it off if its errors are already all publicly exported or this is not applicable):

• abci: export errors  #1185
• blocksync: export errors #1186
• config
• consensus: export errors #1211
• crypto: export errors #1463
• evidence: export errors #1284
• libs
• feat(light): export errors  #1904
• mempool: export errors #1427
• chore: export node package errors #3056
• chore: export p2p package errors #1901
• privval
• feat(proxy): export errors #1899
• refactor(rpc): export rpc package errors #2200
• state
• statesync
• store
• types
• version

Once the packages are implemented:

• Refactor or add new unit tests to use exported errors #2660