Fixes langfuse/langfuse#8176

Pyright flags Langfuse import as private after py.typed was added.

Fix: explicitly re-export in init.py

Disclaimer: Experimental PR review

Greptile Summary

This PR addresses a type checking issue with Pyright that arose after the package was marked as typed with py.typed. The change modifies how the Langfuse class is imported and re-exported in the package's __init__.py file.

What changed:

• Instead of directly importing Langfuse from the private module ._client.client, the code now imports the entire client module as _client
• The Langfuse class is then re-exported through an explicit attribute assignment: Langfuse = _client.Langfuse

Why this change was needed:
Pyright enforces that modules prefixed with underscores (like ._client.client) are private and should not be directly imported from outside the package. When py.typed was added to mark the package as typed, Pyright began flagging the direct import as accessing private internals.

How it fits with the codebase:
This change maintains the exact same public API - users can still import Langfuse from the package root as before. The __all__ list remains unchanged, ensuring the public interface is preserved. This is a common Python pattern for controlling what gets exposed as the public interface while keeping internal module structure private. The change only affects the import mechanism, not the functionality or runtime behavior.

Confidence score: 5/5

• This is a safe cosmetic change that only affects import mechanics without altering functionality
• The fix directly addresses the reported Pyright issue using a well-established Python pattern
• No files need additional attention as this is a straightforward type checker compatibility fix