fix(web-todo): dock-owned selection, keyboard-openable row, documented tail todos field

Three ds-review-bot round-8 findings on the todo display surfaces.

TodoPanel took the whole `useSession` hook and cast the snapshot to reach
`todos`, which put slot plumbing and an unchecked cast inside the presentation
component. The panel now takes `todos: readonly TodoItem[]`; TodoDock does the
selecting, matching the QueueDock posture the dock slot already establishes.

The todo row carried `onClick` with no keyboard route, so its details panel was
mouse-only. It now takes ToolRow's route verbatim: `role="button"`,
`tabIndex={0}`, and an Enter/Space handler that claims the event. The row stays
a `<div>` because a `<button>` flattens its inline spans.

`session.history`'s tail-only `todos` field was documented at the TS signature
but not in the apiproxy README pair, and the Agent Note claimed the feature
added no new wire vocabulary. Both README sides now state the tail/omission
semantics (an omitted field on a tail response is the empty plan, not unchanged
state), and the note records the one added field instead of denying it.

Tests: TodoPanel specs render the plain list; new TodoDock specs cover selection,
live follow, rollback-to-empty, and the registration shape; a new row spec pins
Enter/Space activation and non-activating keys.

packages/client/ui-conversation/src/client/skeleton/TodoPanel.tsx

@@ -1,20 +1,19 @@
 // TodoPanel: persistent plan strip above the composer (the web counterpart
-// of the TUI plan panel). Renders
-// the latest todo/write whole-list snapshot off the session snapshot — no
-// data of its own, hidden while the list is empty. Mounted through the
-// 'conversation.input.dock' slot (QueueDock posture): the standard session
-// kit supplies useSession, so the inner component stays framework-free.
+// of the TUI plan panel). Renders the latest todo/write whole-list snapshot —
+// no data of its own, hidden while the list is empty. Mounted through the
+// 'conversation.input.dock' slot (QueueDock posture): the dock adapter does
+// the selecting, so the panel takes the plain list and stays framework-free.
 
 import { useState } from 'react'
 import type { Context } from 'cordis'
 import type { PropsRuntime } from '@deepseek-ai/dsh-client-ui-slots'
 import type { TodoItem } from '@deepseek-ai/dsh-client-runtime/client'
-import type { UseSession } from '@deepseek-ai/dsh-client-ui-slots'
 import { IconChevronDownOutline14, IconChevronUpOutline14 } from '@deepseek-ai/dsh-client-ui-primitives'
 import css from './TodoPanel.module.css'
 
 export interface TodoPanelProps {
-  useSession: UseSession
+  /** The session's current plan (empty renders nothing) — selected by the dock adapter. */
+  todos: readonly TodoItem[]
 }
 
 /** Status glyphs mirror the TUI plan panel (✓ done / ● active / ○ pending). */
@@ -22,8 +21,7 @@ const STATUS_GLYPHS: Record<TodoItem['status'], string> = {
   completed: '✓', in_progress: '●', pending: '○',
 }
 
-export function TodoPanel({ useSession }: TodoPanelProps) {
-  const todos = useSession(s => (s as { todos: readonly TodoItem[] }).todos)
+export function TodoPanel({ todos }: TodoPanelProps) {
   const [collapsed, setCollapsed] = useState(false)
   if (todos.length === 0) return null
 
@@ -64,9 +62,10 @@ export function TodoPanel({ useSession }: TodoPanelProps) {
 /** Full props of a dock entry: InputZone owner share + session standard kit + global seat. */
 export type TodoDockProps = PropsRuntime<'conversation.input.dock'>
 
-/** Dock adapter: the standard kit's useSession feeds the strip. */
+/** Dock adapter: selects the plan off the session snapshot and hands the strip a plain list. */
 export function TodoDock({ useSession }: TodoDockProps) {
-  return <TodoPanel useSession={useSession} />
+  const todos = useSession(s => s.todos)
+  return <TodoPanel todos={todos} />
 }
 
 /**

packages/client/ui-conversation/src/client/toolviews/todo-row.tsx

@@ -5,6 +5,7 @@
 // durable list itself renders in the TodoPanel above the composer, so the
 // row stays one line.
 
+import type { KeyboardEvent } from 'react'
 import type { Context } from 'cordis'
 import { StateDot } from '@deepseek-ai/dsh-client-ui-primitives'
 import type { ToolRowProps } from '../contract/slots.ts'
@@ -46,8 +47,23 @@ export function TodoRow({ toolName, block, openDetails }: ToolRowProps) {
   const model = toolRowModel(toolName, block)
   const argsRaw = ('kind' in block ? block.call?.argsRaw : block.argsRaw) ?? ''
   const summary = summarize(argsRaw) ?? model.summary
+  // Button semantics, not a <button>: the row carries inline spans a button
+  // would flatten, and ToolRow takes the same role/tabIndex/Enter-Space route.
+  const openFromKeyboard = (event: KeyboardEvent<HTMLDivElement>) => {
+    if (event.key !== 'Enter' && event.key !== ' ') return
+    event.preventDefault()
+    openDetails()
+  }
   return (
-    <div className={css.row} data-sample="todo-row" data-state={model.state} onClick={openDetails}>
+    <div
+      className={css.row}
+      data-sample="todo-row"
+      data-state={model.state}
+      role="button"
+      tabIndex={0}
+      onClick={openDetails}
+      onKeyDown={openFromKeyboard}
+    >
       {model.state === 'ok'
         ? <span className={css.badge} aria-hidden>☰</span>
         : <StateDot state={model.state === 'running' ? 'ongoing' : model.state === 'stopped' ? 'warning' : 'error'} />}