feat(python): generate Pydantic models and basic catalog for A2UI spec v1.0

[nan-yu]

Description

This PR is Layer 6 in the stacked PR series to implement comprehensive multi-version support and A2UI v1.0 execution in Python.

It generates and registers the strongly typed Pydantic data models and basic catalog definitions for A2UI protocol v1.0:

• Schema Models (python/a2ui_core/src/a2ui/core/schema/v1_0/):

  • constants.py: Spec version constants (SPEC_VERSION = "v1.0").
  • common_types.py: StrictBaseModel, dynamic value types (DynamicString, DynamicNumber, DynamicBoolean, DynamicValue), DataBinding, FunctionCall, FunctionResponse, ComponentCommon, AccessibilityAttributes.
  • agent_to_renderer.py: Modern outbound messages (CreateSurfaceMessage, UpdateComponentsMessage, UpdateDataModelMessage, DeleteSurfaceMessage, CallRendererFunctionMessage, AgentFunctionResponseMessage, AgentToRendererMessage).
  • renderer_to_agent.py: Modern inbound messages (A2uiRendererActionMessage, CallAgentFunctionMessage, RendererFunctionResponseMessage, A2uiClientErrorMessage, RendererToAgentMessage).
  • renderer_capabilities.py: A2uiRendererCapabilities, V10Capabilities, InlineCatalog, FunctionDefinition, ValidationResult.
  • __init__.py: Version export namespace and backward-compatibility aliases.

• Basic Catalog (python/a2ui_core/src/a2ui/core/basic_catalog/v1_0/):

  • components.py: 18 basic component models (TextComponent, ButtonComponent, VideoComponent, SliderComponent, TextFieldComponent, etc.) and BASIC_COMPONENTS registration map.
  • function_apis.py: 14 basic function APIs with dynamic arguments (RequiredApi, RegexApi, LengthApi, OpenUrlApi, AndApi, OrApi, NotApi, etc.).
  • __init__.py: BasicCatalog class bound to v1.0 basic catalog ID.

• Multi-Version Protocol Root (python/a2ui_core/src/a2ui/core/schema/__init__.py):

  • Registered V1_0 = "v1.0" in A2uiProtocolVersion enum.
  • Updated multi-version envelope unions:

    AgentToRendererMessage = Union[
        v0_8.ServerToClientMessage,
        v0_9.ServerToClientMessage,
        v1_0.AgentToRendererMessage,
    ]
    RendererToAgentMessage = Union[
        v0_8.ClientToServerMessage,
        v0_9.ClientToServerMessage,
        v1_0.RendererToAgentMessage,
    ]

• Generator Enhancements (codegen_pydantic.py):

  • Dynamic common_types import computation based on actual symbols used in generated modules.
  • Strictly conditional generation of styles.py and FunctionDefinition based on schema definitions.

---

The Stack

• #2285: feat(skills): add automated Pydantic model generator skill for A2UI schemas
• #2299: feat(python): establish versioned schema architecture and multi-version envelope unions
• #2301: feat(python): generate Pydantic model classes and basic catalog for A2UI spec v0.9
• #2303: feat(python): generate Pydantic model classes and basic catalog for A2UI spec v0.8
• ➔ This PR: feat(python): generate Pydantic models and basic catalog for A2UI spec v1.0

---

Verification

• uv run pyink --check .: Passed
• uv run --all-packages mypy .: Passed (106 source files checked, 0 errors)
• uv run pytest python/: Passed (722 passed, 2 skipped)

TAG=agy
CONV=707c9b6b-b2da-4940-ba6e-67f0b4f1d563

[gemini-code-assist]

Code Review

This pull request adds support for version 1.0 of the A2UI protocol, introducing auto-generated Pydantic models, components, and function APIs for v1_0, and updating multi-version protocol unions. Feedback on the changes highlights two key issues in the code generator: first, a regression where FunctionDefinition in v1_0 compiles to a StrictBaseModel that forbids extra properties, which should be fixed by dynamically injecting additionalProperties: True; second, a potential false positive in import matching where simple substring checks can incorrectly match shorter type names (like DynamicString inside DynamicStringList), which should be resolved using word boundary matching.