fix: Replace Unicode symbols with ASCII on Windows for better compability

[emmettlu]

Related Issue

#499

[Copilot]

Pull request overview

This PR addresses issue #499 by replacing Unicode emoji symbols with ASCII characters in Windows terminals to fix display-width mismatches with prompt-toolkit that cause visual cursor alignment issues.

Key changes:

• Adds platform detection to conditionally use ASCII symbols on Windows (>, $, ?) instead of Unicode emoji (✨, $, 💫)
• Preserves original Unicode symbols for non-Windows platforms

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[Copilot]

The intermediate private variables (_prompt_symbol, _prompt_symbol_shell, _prompt_symbol_thinking) can be eliminated by directly assigning to the final constants within the if/else block. This would simplify the code and reduce the number of variables in the module namespace.

Suggested change

	_prompt_symbol: str
	_prompt_symbol_shell: str
	_prompt_symbol_thinking: str
	if sys.platform == "win32":
	# On Windows terminals, emoji and some wide Unicode symbols can cause
	# display-width mismatches with prompt-toolkit, leading to visual cursor
	# shifts. Use plain ASCII / single-width symbols for better compatibility.
	_prompt_symbol = ">"
	_prompt_symbol_shell = "$"
	_prompt_symbol_thinking = "?"
	else:
	_prompt_symbol = "✨"
	_prompt_symbol_shell = "$"
	_prompt_symbol_thinking = "💫"
	PROMPT_SYMBOL = _prompt_symbol
	PROMPT_SYMBOL_SHELL = _prompt_symbol_shell
	PROMPT_SYMBOL_THINKING = _prompt_symbol_thinking
	PROMPT_SYMBOL: str
	PROMPT_SYMBOL_SHELL: str
	PROMPT_SYMBOL_THINKING: str
	if sys.platform == "win32":
	# On Windows terminals, emoji and some wide Unicode symbols can cause
	# display-width mismatches with prompt-toolkit, leading to visual cursor
	# shifts. Use plain ASCII / single-width symbols for better compatibility.
	PROMPT_SYMBOL = ">"
	PROMPT_SYMBOL_SHELL = "$"
	PROMPT_SYMBOL_THINKING = "?"
	else:
	PROMPT_SYMBOL = "✨"
	PROMPT_SYMBOL_SHELL = "$"
	PROMPT_SYMBOL_THINKING = "💫"

[emmettlu]

No, it causes warns when using basedpyright as the language server