fix Language server does not expose read/write metadata for symbols #3246

[asukaminato0721]

Summary

Fixes #3246

Document highlights now set LSP DocumentHighlightKind::WRITE for assignment/declaration-style references and READ for normal uses.

Test Plan

add test

[Copilot]

Pull request overview

Fixes document highlight responses to include read/write metadata (DocumentHighlight.kind) so editors can apply distinct highlighting for reads vs writes (addresses #3246).

Changes:

• Populate DocumentHighlight.kind as READ vs WRITE based on whether the reference is a write context.
• Track attribute expression context (Load/Store/Del) so attribute writes can be classified correctly.
• Add/adjust LSP interaction tests to assert the returned highlight kind for both regular files and notebook cells.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
pyrefly/lib/lsp/non_wasm/server.rs	Sets DocumentHighlight.kind to READ/WRITE for each highlighted reference.
pyrefly/lib/state/lsp.rs	Stores attribute expr context and adds a helper to classify a reference as write vs read.
pyrefly/lib/test/lsp/lsp_interaction/document_highlight.rs	New test asserting read/write kind values are present in highlight responses.
pyrefly/lib/test/lsp/lsp_interaction/notebook_document_highlight.rs	Updates existing notebook highlight test expectations to include kind.
pyrefly/lib/test/lsp/lsp_interaction/mod.rs	Registers the new document_highlight test module.

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[kinto0]

approach looks great, thanks for picking this up!

just a few code style suggestions

[github-actions]

According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅

[kinto0]

thank you!! very clean

[meta-codesync]

@kinto0 has imported this pull request. If you are a Meta employee, you can view this in D103052266.