Implement lazy loading to defer metadata RPCs until data access time …

[pvrraju]

Hi @alxmrs,

Added lazy loading (issue #44):

lazy_load=True option

Defers metadata RPCs → faster large dataset opens

Backward compatible + tested

can you review my PR?

[pvrraju]

Hi @alxmrs I've addressed all the feedback from the review:

1. Pass lazy_load as an argument to get_info() instead of using getattr
2. Replaced the magic number with proper key sets to check cache status
3. Extracted property fetching into a separate helper method _fetch_collection_properties()
4. Used time.perf_counter() instead of time.time() in tests for more accurate timing
5. Refactored the caching system to use a more consistent approach

Let me know if there's anything else I should adjust!

[jdbcode]

Thanks @pvrraju and @alxmrs! Let's revisit this after #275 is in a pre or stable release.