fix mm input_tokens=0 when server return prompt_tokens

[wenba0]

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• Bugfix（Bug 修复）
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Related Issue | 关联 Issue
Fixes #298

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[gemini-code-assist]

Code Review

This pull request updates the logic for determining input_tokens in the performance summarizer to prioritize existing service-returned values. The reviewer suggested refactoring the conditional logic to improve readability and reduce redundant dictionary lookups using a more idiomatic structure.

[gemini-code-assist]

The logic for determining input_tokens can be simplified to improve readability and avoid redundant dictionary lookups. The current structure using a pass block followed by multiple elif conditions is less idiomatic. Additionally, the comment on line 155 refers to prompt_tokens while the code uses input_tokens, which might be slightly confusing for maintainers.

Suggested change

	if perf_data.get("input_tokens") is not None and perf_data.get("input_tokens") > 0:
	pass # Prefer service-returned "prompt_tokens".
	elif is_mm_prompt(perf_data["input"]):
	perf_data["input_tokens"] = 0 # multi-modal input does not support input_tokens
	elif "input_tokens" not in perf_data or perf_data.get("input_tokens") is None:
	perf_data["input_tokens"] = len(tokenizer.encode(perf_data["input"])) # input_tokens is not provided, calculate it
	input_tokens = perf_data.get("input_tokens")
	if input_tokens is None or input_tokens <= 0:
	if is_mm_prompt(perf_data["input"]):
	perf_data["input_tokens"] = 0 # multi-modal input does not support input_tokens
	elif input_tokens is None:
	# input_tokens is not provided, calculate it
	perf_data["input_tokens"] = len(tokenizer.encode(perf_data["input"]))