Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

[Unreleased]

:a2a_sync_timeout setting for A2UI.A2A, bounding how long the adapter waits for a synchronization acknowledgement and for buffered A2UI parts to drain. Compile-time, defaulting to 5_000 ms:
```
config :a2ui, :a2a_sync_timeout, 5_000
```
Neither timeout is fatal: a synchronization that times out continues processing, and a drain that times out yields a response carrying no buffered A2UI parts.

Requires a2a ~> 0.3.0, up from ~> 0.2. A2A 0.3 is that library's v1.0 protocol release: streaming events moved to the StreamResponse wrapper, A2A errors carry a google.rpc.ErrorInfo array, and message/stream is gated on a declared streaming capability. A2UI uses only the synchronous A2A path — send_message, cancel_task and A2A.Part.Data — so none of that reaches this library and no code changed.
The requirement is now pinned to a single A2A minor rather than the whole 0.x range. A2A is pre-1.0 and ships breaking changes in minor releases, so ~> 0.2 would have let 0.3's wire changes land here unannounced — and ~> 0.3 would do the same for 0.4. A2A 0.2.x is no longer supported.

A2UI.Agent behaviour and use A2UI.Agent macro for building agents with minimal boilerplate
A2UI.Agent.send_message/2 and send_messages/2 helpers for agent-to-client messaging
A2UI.Connection opaque handle for transport-agnostic client connections
SSE + JSON-RPC HTTP transport: A2UI.Plug, A2UI.Plug.SSE, A2UI.Plug.JSONRPC, A2UI.Plug.ConnectionRegistry
A2UI.Transport.SSE client-side transport for connecting to SSE endpoints
A2A protocol transport binding: A2UI.A2A server adapter, A2UI.Transport.A2A client transport (optional dep on :a2a ~> 0.2)
A2UI.Protocol.Messages.Error message type for client-to-server error feedback
A2UI.Catalog module for compile-time component type validation against catalog schemas

Agents track connections as %{id => Connection.t()} map instead of MapSet of PIDs (breaking for custom agent implementations that relied on the internal connection tracking format)
Demo agent refactored to use A2UI.Agent behaviour

A2UI v0.9 protocol types: Surface, Component, DataModel, Messages
JSONL parser for protocol message streams
JSON Pointer (RFC 6901) implementation for data model access
Data binding with path resolution and function call descriptors
Component tree management with template expansion
Surface manager for pure-functional state management
Phoenix function components for all A2UI component types
LiveView integration with two-way data binding and action dispatch
Transport behaviour with local process-messaging implementation
Video and AudioPlayer components
Client-side validation via JS hooks (required, regex, length, numeric, email)
Client-side formatting functions (formatString, formatNumber, formatCurrency, formatDate, pluralize)
Server-side function evaluation (formatString, formatNumber, formatCurrency, formatDate, pluralize, boolean logic)
JS interactivity hooks (A2UITabs, A2UIModal, A2UISubmit, A2UIValidation)
Theming support via CSS variables (primaryColor, iconUrl, agentDisplayName)
Local action support (openUrl, client-side function calls on Button)
Demo application with mix a2ui.demo

README: corrected component count (16 → 18), removed completed items from "Not Yet Implemented"
SPEC.md: added Known Gaps section documenting unimplemented spec features