Add configurable TLS feature flags for reqwest

[cmackenzie1]

Summary

This change introduces configurable TLS feature flags to allow users to choose their preferred TLS implementation when using this library, rather than being locked into rustls-tls.

Key Changes

• Added a new [features] section to Cargo.toml with multiple TLS options:
  • rustls-tls (default): Uses rustls with system roots
  • rustls-tls-native-roots: Uses rustls with native certificate roots
  • native-tls: Uses the platform's native TLS implementation
  • native-tls-vendored: Uses vendored native TLS
• Updated the reqwest dependency to remove the hardcoded rustls-tls feature
• TLS feature selection is now delegated to Cargo's feature resolution system

Implementation Details

• The default feature remains rustls-tls to maintain backward compatibility
• Users can now opt into alternative TLS implementations by specifying features when adding this crate as a dependency
• The reqwest dependency now only explicitly requires the json feature, with TLS features being optional and controlled by this crate's feature flags

https://claude.ai/code/session_014PcmRepV7DMLBi2TnVfoPo

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.29%. Comparing base (06efdf1) to head (5d0997a).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #43   +/-   ##
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  Coverage   88.29%   88.29%           
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  Files           3        3           
  Lines         547      547           
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  Hits          483      483           
  Misses         64       64           

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