chore: clean up legacy tool/UI code paths and remove unused events

apps/lib/core/chat/ag_ui_event.dart

@@ -9,7 +9,6 @@ class AgUiEventTypeWire {
   static const toolCallArgs = 'TOOL_CALL_ARGS';
   static const toolCallEnd = 'TOOL_CALL_END';
   static const toolCallResult = 'TOOL_CALL_RESULT';
-  static const toolCallError = 'TOOL_CALL_ERROR';
 }
 
 enum AgUiEventType {
@@ -23,7 +22,6 @@ enum AgUiEventType {
   toolCallArgs,
   toolCallEnd,
   toolCallResult,
-  toolCallError,
   unknown,
 }
 
@@ -38,7 +36,6 @@ const _wireToTypeMap = {
   AgUiEventTypeWire.toolCallArgs: AgUiEventType.toolCallArgs,
   AgUiEventTypeWire.toolCallEnd: AgUiEventType.toolCallEnd,
   AgUiEventTypeWire.toolCallResult: AgUiEventType.toolCallResult,
-  AgUiEventTypeWire.toolCallError: AgUiEventType.toolCallError,
 };
 
 const _typeToWireMap = {
@@ -52,7 +49,6 @@ const _typeToWireMap = {
   AgUiEventType.toolCallArgs: AgUiEventTypeWire.toolCallArgs,
   AgUiEventType.toolCallEnd: AgUiEventTypeWire.toolCallEnd,
   AgUiEventType.toolCallResult: AgUiEventTypeWire.toolCallResult,
-  AgUiEventType.toolCallError: AgUiEventTypeWire.toolCallError,
   AgUiEventType.unknown: '',
 };
 
@@ -82,7 +78,6 @@ abstract class AgUiEvent {
       AgUiEventType.toolCallArgs => ToolCallArgsEvent.fromJson(json),
       AgUiEventType.toolCallEnd => ToolCallEndEvent.fromJson(json),
       AgUiEventType.toolCallResult => ToolCallResultEvent.fromJson(json),
-      AgUiEventType.toolCallError => ToolCallErrorEvent.fromJson(json),
       AgUiEventType.unknown => UnknownAgUiEvent(rawJson: json),
     };
   }
@@ -162,14 +157,12 @@ class TextMessageEndEvent extends AgUiEvent {
     required this.answer,
     required this.role,
     required this.status,
-    required this.uiSchema,
   }) : super(type: AgUiEventType.textMessageEnd);
 
   final String messageId;
   final String answer;
   final String role;
   final String status;
-  final Map<String, dynamic>? uiSchema;
 
   factory TextMessageEndEvent.fromJson(Map<String, dynamic> json) =>
       TextMessageEndEvent(
@@ -177,7 +170,6 @@ class TextMessageEndEvent extends AgUiEvent {
         answer: _asString(json['answer']),
         role: _asString(json['role'], fallback: 'assistant'),
         status: _asString(json['status'], fallback: 'success'),
-        uiSchema: _asMap(json['ui_schema']),
       );
 }
 
@@ -247,22 +239,6 @@ class ToolCallResultEvent extends AgUiEvent {
       );
 }
 
-class ToolCallErrorEvent extends AgUiEvent {
-  ToolCallErrorEvent({required this.toolCallId, required this.error, this.code})
-    : super(type: AgUiEventType.toolCallError);
-
-  final String toolCallId;
-  final String error;
-  final String? code;
-
-  factory ToolCallErrorEvent.fromJson(Map<String, dynamic> json) =>
-      ToolCallErrorEvent(
-        toolCallId: _asString(json['toolCallId']),
-        error: _asString(json['error'], fallback: 'Tool call failed'),
-        code: json['code'] as String?,
-      );
-}
-
 class HistorySnapshot {
   const HistorySnapshot({
     required this.scope,