Add __repr__ to custom PS1 class

[iBug]

During my debugging and implementation of #25521, I find a descriptive __repr__() for the custom PS1 object very helpful, so this PR comes as an addition for #25521.

[eleanorjboyd]

@anthonykim1 lmk when you need my review here

[Copilot]

Pull request overview

This PR adds a __repr__ method to the PS1 class in pythonrc.py to improve debugging experience during development and implementation work related to issue #25521.

Key Changes:

• Added __repr__ method to the PS1 class that returns a descriptive string representation

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[Copilot]

The __repr__ method should follow Python conventions by including the class name. A typical pattern for __repr__ when the object cannot be recreated from the string is <ClassName: description>. Consider changing this to something like <PS1: Custom PS1 for VS Code Python Shell Integration> or <pythonrc.PS1 object at {hex(id(self))}> to make it clearer what type of object this represents.

Suggested change

	return "<Custom PS1 for VS Code Python Shell Integration>"
	return "<PS1: Custom PS1 for VS Code Python Shell Integration>"

[Copilot]

The new __repr__ method lacks test coverage. Since the PS1 class already has comprehensive tests in test_shell_integration.py covering __str__ and other functionality, a test should be added to verify that repr(ps1) returns the expected string representation. This ensures the debugging enhancement mentioned in the PR description works as intended.