Update lib hooks

[eminano]

This PR updates the hooks that allow to customise the use for the pgstream library:

• Add support to use a custom search index name adapter and a mapper
• Add granularity to filter wal data and schema events separately

Small improvements included:

• Update of pgx dependency
• Removal of panic during log entry unmarshaling
• Apply search store retry logic by default (if no config is provided, there's a default that applies). If no retries are required, then the config must be explicitly updated accordingly.

The commits have been split for ease of reviewing.