Clean up inefficient String variants in error types

[seanchen1991]

Feature Summary

Application and client-specific errors (like those in 07-tendermint) often get converted to strings and end up in variants like Other or ClientSpecific within lower-level error enums. This approach not only leads to large memory allocations but also makes it difficult for hosts to traverse the error structure to extract or check the specific data they need. Instead, they are forced to parse these strings, which is cumbersome and inefficient.

Proposal

Clean up and/or consolidate these error variants such that their semantics give a better idea of the underlying error.