refactor: remove executeCommand in favor of standard run/stream path

packages/server/src/shared/messages.ts

@@ -941,14 +941,6 @@ export const ListCommandsRequestSchema = z.object({
   requestId: z.string(),
 });
 
-export const ExecuteCommandRequestSchema = z.object({
-  type: z.literal("execute_command_request"),
-  agentId: z.string(),
-  commandName: z.string(),
-  args: z.string().optional(),
-  requestId: z.string(),
-});
-
 export const RegisterPushTokenMessageSchema = z.object({
   type: z.literal("register_push_token"),
   token: z.string(),
@@ -1082,7 +1074,6 @@ export const SessionInboundMessageSchema = z.discriminatedUnion("type", [
   ClientHeartbeatMessageSchema,
   PingMessageSchema,
   ListCommandsRequestSchema,
-  ExecuteCommandRequestSchema,
   RegisterPushTokenMessageSchema,
   ListTerminalsRequestSchema,
   SubscribeTerminalsRequestSchema,
@@ -1868,22 +1859,6 @@ export const ListCommandsResponseSchema = z.object({
   }),
 });
 
-const AgentCommandResultSchema = z.object({
-  text: z.string(),
-  timeline: z.array(AgentTimelineItemPayloadSchema),
-  usage: AgentUsageSchema.optional(),
-});
-
-export const ExecuteCommandResponseSchema = z.object({
-  type: z.literal("execute_command_response"),
-  payload: z.object({
-    agentId: z.string(),
-    result: AgentCommandResultSchema.nullable(),
-    error: z.string().nullable(),
-    requestId: z.string(),
-  }),
-});
-
 // ============================================================================
 // Terminal Outbound Messages
 // ============================================================================
@@ -2050,7 +2025,6 @@ export const SessionOutboundMessageSchema = z.discriminatedUnion("type", [
   SpeechModelsListResponseSchema,
   SpeechModelsDownloadResponseSchema,
   ListCommandsResponseSchema,
-  ExecuteCommandResponseSchema,
   ListTerminalsResponseSchema,
   TerminalsChangedSchema,
   CreateTerminalResponseSchema,
@@ -2191,8 +2165,6 @@ export type ClearAgentAttentionMessage = z.infer<typeof ClearAgentAttentionMessa
 export type ClientHeartbeatMessage = z.infer<typeof ClientHeartbeatMessageSchema>;
 export type ListCommandsRequest = z.infer<typeof ListCommandsRequestSchema>;
 export type ListCommandsResponse = z.infer<typeof ListCommandsResponseSchema>;
-export type ExecuteCommandRequest = z.infer<typeof ExecuteCommandRequestSchema>;
-export type ExecuteCommandResponse = z.infer<typeof ExecuteCommandResponseSchema>;
 export type RegisterPushTokenMessage = z.infer<typeof RegisterPushTokenMessageSchema>;
 
 // Terminal message types