impl introduce-parameter refactor

[asukaminato0721]

Summary

Add a new introduce-parameter code action that inserts a parameter, replaces the selected expression, and updates call sites. Includes method/classmethod/staticmethod handling and rejects *args/**kwargs.

Fixes part of #364

https://www.jetbrains.com/help/pycharm/introduce-parameter.html#extract-constant-dialog

Test Plan

Adds comprehensive LSP code action tests for the new behavior.

[Copilot]

Pull request overview

This pull request implements a new "introduce-parameter" code action that extracts a selected expression into a function parameter and automatically updates all call sites. The implementation handles various Python function types including regular functions, methods, classmethods, and staticmethods, and correctly rejects refactoring when the expression uses local variables or when call sites use variadic arguments.

Key Changes:

• New introduce-parameter refactoring with single and "replace all occurrences" variants
• Automatic call site updates with proper parameter substitution
• Support for keyword-only parameter insertion when functions use *args or have keyword-only parameters
• Rejection of unsafe refactorings (local variable usage, variadic call arguments)

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
pyrefly/lib/state/lsp/quick_fixes/introduce_parameter.rs	Core implementation of introduce-parameter refactor with parameter insertion, expression template substitution, and call site updating
pyrefly/lib/state/lsp/quick_fixes/mod.rs	Module declaration for the new introduce_parameter module
pyrefly/lib/state/lsp.rs	Public API method to invoke introduce-parameter code actions
pyrefly/lib/lsp/non_wasm/server.rs	Integration of introduce-parameter actions into LSP server code action handler
pyrefly/lib/test/lsp/code_actions.rs	Comprehensive test suite covering basic functionality, method handling, edge cases, and rejection scenarios
crates/pyrefly_config/src/config.rs	Benign removal of unnecessary lifetime annotation

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[Copilot]

The function documentation is incomplete compared to similar functions in the codebase. Consider expanding it to explain: 1) what the function does (extracts an expression into a parameter and updates call sites), 2) when it returns None (e.g., when the selection is empty, not an exact expression, uses local variables, in parameter list, uses variadic parameters), and 3) what actions are returned (single replacement vs. replace-all-occurrences). See extract_variable_code_actions for a good example of comprehensive documentation.

Suggested change

	/// Builds introduce-parameter refactor actions for a selected expression.
	/// Builds "introduce parameter" refactor code actions for the selected expression.
	///
	/// This refactor extracts the selected expression into a new parameter of the
	/// enclosing function or method, and updates the corresponding call sites to
	/// pass the extracted expression as an argument.
	///
	/// Returns `None` when no valid refactor is available. This includes cases
	/// where:
	/// - the selection is empty or contains only whitespace,
	/// - the selection does not correspond to an exact expression in the AST,
	/// - the selected expression cannot be safely turned into a parameter
	/// (for example, because it depends on local variables, is located in a
	/// parameter list, or conflicts with variadic parameters).
	///
	/// When successful, returns a list of [`LocalRefactorCodeAction`]s. Typically
	/// this will contain actions for introducing a parameter at the current
	/// occurrence of the expression, and (when applicable) introducing a
	/// parameter for all matching occurrences within the same function.

[github-actions]

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

[meta-codesync]

@kinto0 has imported this pull request. If you are a Meta employee, you can view this in D90857425.