[Feature Request]: Add support of file path during query

[MohitTilwani15]

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Feature Request Description

Adding support for a file_path filter on the query endpoint, allowing developers to narrow down the retrieval context when querying LightRAG. By specifying one or more file paths, users can constrain the scope of semantic retrieval and reasoning to a subset of documents relevant to their application.

This enhancement will apply uniformly across entities, relationships, and chunks, ensuring that all retrieval operations respect the provided file path constraints.

Use Case Example:
Developers building on top of LightRAG can now query only within specific documents or folders (e.g., contracts/nda/ or policies/security_policy.pdf) to improve precision, reduce noise, and enhance retrieval efficiency in multi-document environments.

Key Benefits:

• Enables fine-grained context filtering during query and reasoning.
• Improves retrieval relevance by limiting scope to selected file paths.

Additional Context

No response