feat(Agnet): support multi agents (#385)

src/types/agent.ts

@@ -0,0 +1,17 @@
+export interface AgentSummary {
+  id: string;
+  name: string;
+  isDefault: boolean;
+  modelDisplay: string;
+  inheritedModel: boolean;
+  workspace: string;
+  agentDir: string;
+  channelTypes: string[];
+}
+
+export interface AgentsSnapshot {
+  agents: AgentSummary[];
+  defaultAgentId: string;
+  configuredChannelTypes: string[];
+  channelOwners: Record<string, string>;
+}