Redesign pool_info_cache to not use triggers

[rdlrt]

See if we can do without triggers for pool_info_cache , as there can be edge cases (if not using insert/delete).

Alternatively, we can leave triggers as-is , but remove any pool_retire entries from pool_info_cache and add them to specific endpoints that currently rely on pool_info_cache.

A sub-item of fixing this issue also includes updating pool_updates endpoint to change the behaviour of pool_update => pool_status to show status from the specific transaction, rather than current - allowing appropriate maintain of historical information