feat: implement Rust and Python APIs to read file slices

[xushiyan]

• Support python APIs to retrieve the latest file slices
• Support python APIs to read file slice as pyarrow.RecordBatch
• Implement Rust logic to fetch num records in parquet file
• Implement Rust logic to read parquet file into arrow.RecordBatch

Fixes #29

[codecov]

Codecov Report

Attention: Patch coverage is 82.18391% with 31 lines in your changes missing coverage. Please review.

Project coverage is 77.23%. Comparing base (da217e5) to head (31c2d36).

Files	Patch %	Lines
python/src/lib.rs	0.00%	24 Missing ⚠️
crates/datafusion/src/lib.rs	0.00%	5 Missing ⚠️
crates/core/src/table/mod.rs	94.44%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #28      +/-   ##
==========================================
+ Coverage   76.75%   77.23%   +0.48%     
==========================================
  Files          12       12              
  Lines         413      492      +79     
==========================================
+ Hits          317      380      +63     
- Misses         96      112      +16     

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