Update contact multiple surfaces sample

[nan-yu]

Description

It updates the sample to use the A2uiSchemaManager from the a2ui-agent python SDK.

Tested:

• The contact angular client successfully connected to the contact_multiple_surfaces agent and rendered the response correctly.

Pre-launch Checklist

• I signed the CLA.
• I read the Contributors Guide.
• I read the Style Guide.
• I have added updates to the CHANGELOG.
• I updated/added relevant documentation.
• My code changes (if any) have tests.

If you need help, consider asking for advice on the discussion board.

[gemini-code-assist]

Code Review

This pull request introduces a new a2ui-agent Python package with a centralized A2uiSchemaManager for handling A2UI schemas. This is a great architectural improvement, moving away from hardcoded schemas in the sample agents. The manager provides robust, multi-layered logic for loading schemas from package resources or the source repository, and includes functionality for bundling, pruning, and validating schemas. The sample agents (contact_lookup and contact_multiple_surfaces) are refactored to use this new manager, simplifying their code and making them more maintainable. The changes also include a Hatch build hook to package the schema files correctly and new tests for the added functionality.

I've found a couple of issues: one in a __main__ block in contact_lookup/prompt_builder.py that would cause a TypeError if run directly, and a logic error in contact_multiple_surfaces/agent.py where a check for a loaded schema was referencing a method instead of a property. I've provided suggestions to fix both. Overall, this is a well-executed and beneficial refactoring.

[gemini-code-assist]

This check for a loaded schema is incorrect. self._schema_manager.bundle_schemas refers to the method itself, which will never be None. You should check the bundled_schema property instead, which holds the result of the schema bundling. This will ensure the error handling for a missing schema triggers correctly.

Suggested change

	if self.use_ui and self._schema_manager.bundle_schemas is None:
	if self.use_ui and self._schema_manager.bundled_schema is None:

[gemini-code-assist]

The arguments in this block are incorrect and will cause a TypeError when running the script directly.

1. The A2uiSchemaManager constructor does not accept an examples argument. The examples should be passed to the generate_system_prompt method instead.
2. The generate_system_prompt method does not have an include_examples parameter; you should use the examples parameter.

Suggested change

	contact_prompt = A2uiSchemaManager("0.8", examples=CONTACT_UI_EXAMPLES).generate_system_prompt(
	role_description=ROLE_DESCRIPTION,
	workflow_description=WORKFLOW_DESCRIPTION,
	ui_description=UI_DESCRIPTION,
	include_examples=True,
	)
	schema_manager = A2uiSchemaManager("0.8")
	contact_prompt = schema_manager.generate_system_prompt(
	role_description=ROLE_DESCRIPTION,
	workflow_description=WORKFLOW_DESCRIPTION,
	ui_description=UI_DESCRIPTION,
	examples=CONTACT_UI_EXAMPLES,
	)