Add Parameters to Parameter Object refactoring command

[Copilot]

This PR implements a new refactoring tool that converts method calls from passing individual arguments to passing a parameter object (struct/record/class), addressing a common refactoring pattern needed for improved code maintainability.

Features

New Command: parameters-to-object

Converts methods like this:

void MyFunction(bool arg1, string arg2, CustomObject arg3) {
    if (arg1) {
        Console.WriteLine(arg2);
        return arg3.Value;
    }
}

MyFunction(true, "Hello World!", new CustomObject());

Into this:

void MyFunction(MyFunctionArgs args) {
    if (args.arg1) {
        Console.WriteLine(args.arg2);
        return args.arg3.Value;
    }
}

public class MyFunctionArgs {
    public bool arg1 { get; set; }
    public string arg2 { get; set; }
    public CustomObject arg3 { get; set; }
    
    public MyFunctionArgs(bool arg1, string arg2, CustomObject arg3) {
        this.arg1 = arg1;
        this.arg2 = arg2;
        this.arg3 = arg3;
    }
}

Usage

# Convert to class (default)
cast parameters-to-object MyFile.cs --line 10 --parameter-object-name "MyParams"

# Convert to struct  
cast parameters-to-object MyFile.cs --line 10 --parameter-object-type struct

# Convert to record (modern C# syntax)
cast parameters-to-object MyFile.cs --line 10 --parameter-object-type record

# Preview changes
cast parameters-to-object MyFile.cs --line 10 --dry-run

Implementation Details

• Method Signature Transformation: Updates method to accept single parameter object
• Method Body Updates: Replaces parameter references with args.parameterName syntax
• Parameter Object Generation: Creates class/struct/record with properties and constructor
• Type Support: Handles complex types including generics and custom objects
• Validation: Blocks unsupported parameter types (ref/out/in/params)

Testing

Added comprehensive test suite with 5 test cases covering:

• Basic parameter conversion for all object types
• Complex parameter types (generics, collections)
• Error handling for methods without parameters
• Real-world business logic scenarios

All existing tests (78) continue to pass.

Current Limitations

• Call site updates require manual intervention (noted for future enhancement)
• Some edge cases in complex parameter reference replacement may need manual review

Fixes #19.

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[AdamFrisby]

@copilot we need the update callers functionality as well.

[Copilot]

@copilot we need the update callers functionality as well.

I've implemented the update callers functionality. The refactoring command now automatically finds and updates all call sites to use the new parameter object.

Key features added:

• Automatic call site conversion: MyFunction(arg1, arg2) → MyFunction(new MyFunctionArgs(arg1, arg2))
• --update-callers option (defaults to true) to control this behavior
• Support for all parameter object types (class/struct/record)
• Comprehensive test coverage including multiple call sites

The implementation includes proper constructor assignments using this.property = parameter syntax and maintains backward compatibility for users who prefer manual call site updates.

Commit: b4ead92