[Frontend] Complete Redesign of Tool Calling

[chaunceyjiang]

Fix #22918

Purpose

Test Plan

Test Result

(Optional) Documentation Update

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Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.

[gemini-code-assist]

Code Review

This pull request refactors the tool calling JSON schema generation and introduces a new generic tool parser. My review identified a critical issue in protocol.py where return statements were missing, causing incorrect logic for tool choices. I've also found that the new GenericToolParser has an incomplete streaming implementation with leftover debugging code. I've provided suggestions to fix these issues.

[gemini-code-assist]

This streaming implementation appears to be incomplete. It contains debugging print statements that should be removed. The core logic for handling tool calls in streaming mode is commented out, and the function currently only streams back content, which will not work for tool calls. Additionally, most of the method's parameters are unused. I've suggested cleaning up the implementation to reflect its current capabilities.

Suggested change

	print(f"delta_text: {delta_text}")
	print(f"previous_text {previous_text} ")
	print(f"current_text {current_text} ")
	# delta = DeltaMessage(tool_calls=[
	# DeltaToolCall(index=self.current_tool_id,
	# function=DeltaFunctionCall(
	# arguments=delta_text).model_dump(
	# exclude_none=True))
	# ])
	delta = DeltaMessage(content=delta_text)
	return delta
	# TODO: Implement streaming for tool calls.
	# The current implementation only handles content streaming.
	delta = DeltaMessage(content=delta_text)
	return delta

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