Refactor extension config

[dentiny]

Is your feature request related to a problem? Please describe. The config part is the piece im most unsatisfied with: https://github.com/dentiny/duck-read-cache-fs/blob/main/src/include/cache_filesystem_config.hpp It checks and updates every open operation, which leaves messy parse, extraction and update operation.

Describe the solution you'd like A better solution is to register a callback on config change.

Describe alternatives you've considered N/A

Additional context Need to confirm whether config params are valid.