A2uiSurface

Renders one A2UI surface from a snapshot. Given the store as surfaces, its input components write edits into that store; the application keeps passing the store's current snapshot. Edits stay local. A pressed Button hands its resolved action message to onAction, and the application transports it. A press is blocked while any input's checks fail; the failing inputs then show their messages until they pass. A Button whose own checks fail is disabled. A Button with a function-call action runs it here, through functions or the built-in openUrl, without consulting checks on inputs. Function-call props show their current value. A component the catalog lacks keeps its children. A child template is stamped once per item of its list; inputs, checks and actions inside it work on that item. The surface's theme sets the accent colour from a hex primaryColor and shows agentDisplayName and iconUrl as a small line above the content.