feat(web): add workspace-aware session flow

packages/host/apiproxy/src/fetch/client.ts

@@ -21,6 +21,10 @@ import {
   sessionListValueSchema,
   sessionPromptValueSchema,
 } from '../api/sessions.schema.ts'
+import {
+  workspaceCreateValueSchema,
+  workspaceListValueSchema,
+} from '../api/workspace.schema.ts'
 
 /**
  * Client consumption face of the contract (shape a): same domain tree as ApiProxy, but unary
@@ -48,6 +52,10 @@ export interface IApiClient {
   host: {
     describe(payload: RequestPayload<'host.describe'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'host.describe'>>>
   }
+  workspace: {
+    list(payload: RequestPayload<'workspace.list'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.list'>>>
+    create(payload: RequestPayload<'workspace.create'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.create'>>>
+  }
   events: {
     mux(payload: Parameters<ApiProxy['events']['mux']>[0]['payload'], signal: AbortSignal, onOpen?: () => void): AsyncIterable<RpcRequest<MuxFrame>>
     host(payload: Parameters<ApiProxy['events']['host']>[0]['payload'], signal: AbortSignal, onOpen?: () => void): AsyncIterable<RpcRequest<HostFrame>>
@@ -67,6 +75,8 @@ const UNARY_VALUE_SCHEMAS: { [K in keyof RpcMethodMap]: z.ZodType<Wire<ResponseV
   'session.prompt': sessionPromptValueSchema,
   'session.cancel': sessionCancelValueSchema,
   'host.describe': hostDescribeValueSchema,
+  'workspace.list': workspaceListValueSchema,
+  'workspace.create': workspaceCreateValueSchema,
 }
 
 /** Default unary timeout (rpc-compare 2026-07-19: a hung host must not leave callers pending forever). */
@@ -253,6 +263,11 @@ export abstract class AbstractApiClient implements IApiClient {
     describe: (payload, signal) => this.callUnary('host.describe', payload, signal),
   }
 
+  readonly workspace: IApiClient['workspace'] = {
+    list: (payload, signal) => this.callUnary('workspace.list', payload, signal),
+    create: (payload, signal) => this.callUnary('workspace.create', payload, signal),
+  }
+
   readonly events: IApiClient['events'] = {
     mux: (payload, signal, onOpen) => this.openMux(payload, signal, onOpen),
     host: (payload, signal, onOpen) => this.openHost(payload, signal, onOpen),