feat(web): session list one-list, hover card, row menus, rename, manual ordering

Sidebar session list grows the figma 239-10458 feature set and the
workspace/session browsing region moves wholesale into ui-workspace:

- Group-by menu (WorkSpace / In one list): flat mode lists every session
  top-level, strictly newest-first; the choice persists across reloads.
- Session rows get a 500ms hover detail card (title / relative time /
  status line) and a ... menu (Rename / Fork session / Delete session,
  visual-only for now); workspace headers get ... with Rename (wired) and
  Delete workspace (visual-only).
- workspace.rename RPC: trims, rejects duplicate titles on the create
  chain (workspace-name-conflict), no-op on same title; modal dialog with
  client-side duplicate pre-check.
- workspace.insertSessionBefore RPC (DOM-insertBefore semantics, omitted
  anchor appends): HTML5 drag reorder of root sessions inside a workspace
  group; order truth stays host-side, the view refreshes from the
  response/changed frame.
- Activity pinning removed: the session/event touchSession chain is gone;
  workspace accounts are manually owned (new sessions prepend, explicit
  reordering only). Contracts and tests updated, api catalog regenerated.
- ui-sidebar reduced to the column shell (brand, fold state machine, New
  Session, Settings) exposing one sidebar.workspaces hole with a two-fact
  owner share {wide, expandSidebar}; ui-workspace owns the whole region
  (header, search, grouped/flat lists, dialogs, drag) plus the picker via
  a shared WorkspaceCreateFlow. The old sidebar.workspace picker slot and
  its deferral indirection are gone.
- ui-primitives: Menu gains label entries, danger rows, and
  closeOnPointerLeave; new HoverCard (portaled, open-delay, disabled
  guard). Hover card and row menu never coexist.

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

@@ -23,7 +23,9 @@ import {
 } from '../api/sessions.schema.ts'
 import {
   workspaceCreateValueSchema,
+  workspaceInsertSessionBeforeValueSchema,
   workspaceListValueSchema,
+  workspaceRenameValueSchema,
 } from '../api/workspace.schema.ts'
 
 /**
@@ -55,6 +57,8 @@ export interface IApiClient {
   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'>>>
+    rename(payload: RequestPayload<'workspace.rename'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.rename'>>>
+    insertSessionBefore(payload: RequestPayload<'workspace.insertSessionBefore'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.insertSessionBefore'>>>
   }
   events: {
     mux(payload: Parameters<ApiProxy['events']['mux']>[0]['payload'], signal: AbortSignal, onOpen?: () => void): AsyncIterable<RpcRequest<MuxFrame>>
@@ -77,6 +81,8 @@ const UNARY_VALUE_SCHEMAS: { [K in keyof RpcMethodMap]: z.ZodType<Wire<ResponseV
   'host.describe': hostDescribeValueSchema,
   'workspace.list': workspaceListValueSchema,
   'workspace.create': workspaceCreateValueSchema,
+  'workspace.rename': workspaceRenameValueSchema,
+  'workspace.insertSessionBefore': workspaceInsertSessionBeforeValueSchema,
 }
 
 /** Default unary timeout (rpc-compare 2026-07-19: a hung host must not leave callers pending forever). */
@@ -266,6 +272,8 @@ export abstract class AbstractApiClient implements IApiClient {
   readonly workspace: IApiClient['workspace'] = {
     list: (payload, signal) => this.callUnary('workspace.list', payload, signal),
     create: (payload, signal) => this.callUnary('workspace.create', payload, signal),
+    rename: (payload, signal) => this.callUnary('workspace.rename', payload, signal),
+    insertSessionBefore: (payload, signal) => this.callUnary('workspace.insertSessionBefore', payload, signal),
   }
 
   readonly events: IApiClient['events'] = {