fix: review-bot findings on the provider-hosted shell

- Keep ConversationSession mounted for blank sessions (chrome-less) so the
  draft-persistence mirror stays bound in the hero; hero typing reaches the
  chat store again.
- Restore the baselines-ready gate in AppFrame: empty boot snapshots no
  longer flash the New Workspace hero before either baseline lands.
- Commit ordinary sends through the machine (send-committed event +
  Shell.commitSend): undo can no longer resurrect already-sent content on
  the default-sink path.
- Give the production InputMachine a real wall clock so the typing-run
  merge window actually expires.
- Coalesce concurrent connectWorkspace creates per workspace: the summary
  has no cwd until the host frame lands, so a second New Session inside
  that window minted a duplicate hidden blank session.

packages/client/ui-conversation/src/client/input/contract.ts

@@ -250,6 +250,8 @@ export type InputEvent =
   | { readonly type: 'adjudicated'; readonly attempt: SubmitAttempt; readonly outcome: PickOutcome }
   | { readonly type: 'adjudication-failed'; readonly attempt: SubmitAttempt; readonly message: string }
   | { readonly type: 'submit-settled'; readonly attempt: SubmitAttempt; readonly ok: boolean; readonly outcome?: SubmitOutcome; readonly message?: string }
+  /** An ordinary (default-sink) send was accepted: clear the draft as a COMMIT — undo must not resurrect sent content (mirrors the command submit-settled success arm). */
+  | { readonly type: 'send-committed' }
   | { readonly type: 'release' }
 
 /**

packages/client/ui-conversation/src/client/input/facade.ts

@@ -71,7 +71,9 @@ export class SessionInputShell implements SessionInput {
     submit: (mode) => { this.submit(mode) },
   }
 
-  private readonly core = new InputMachine()
+  // Real wall clock: the typing-run merge window must actually expire in
+  // production (the machine's no-clock default is a constant for pure tests).
+  private readonly core = new InputMachine({ now: () => Date.now() })
   private noticeSeq = 0
   private lastDraft = ''
   private disposed = false
@@ -95,6 +97,15 @@ export class SessionInputShell implements SessionInput {
     this.run(this.core.dispatch({ type: 'draft-changed', draft: text, ...(editRange !== undefined ? { editRange } : {}) }))
   }
 
+  /**
+   * Clear the draft as a successful-send commit: no undo unit is recorded and
+   * the undo history is cut, so Ctrl/Cmd-Z cannot resurrect sent content
+   * (the command path gets the same discipline from submit-settled success).
+   */
+  commitSend(): void {
+    this.run(this.core.dispatch({ type: 'send-committed' }))
+  }
+
   /**
    * Insert a newline at the selection as one machine transaction (the
    * execCommand path is gone — a second undo history would fork).

packages/client/ui-conversation/src/client/input/hub.ts

@@ -116,7 +116,8 @@ export class InputHub implements InputService {
   private sink(session: Session, text: string, mode: 'queue' | 'steer'): void {
     if (text === '') return
     const shell = this.shells.get(session.sessionId)
-    shell?.setDraft('')
+    // Commit, not an editable clear: undo must not resurrect sent content.
+    shell?.commitSend()
     void session.prompt([{ type: 'text', text }], mode).then(
       (result) => {
         if (!result.ok && shell?.snapshot.draft === '') shell.setDraft(text)

packages/client/ui-conversation/src/client/input/machine.ts

@@ -167,6 +167,7 @@ export class InputMachine {
       case 'adjudicated': return this.onAdjudicated(ev.attempt, ev.outcome)
       case 'adjudication-failed': return this.onAdjudicationFailed(ev.attempt, ev.message)
       case 'submit-settled': return this.onSubmitSettled(ev)
+      case 'send-committed': return this.onSendCommitted()
       case 'release': return this.onRelease()
       default: return unreachable(ev)
     }
@@ -542,6 +543,19 @@ export class InputMachine {
     return [{ type: 'notice', level: 'error', text }]
   }
 
+  /** Ordinary send accepted: clear as a commit (no undo unit; sent content
+   *  must not be resurrectable — same discipline as submit-settled success). */
+  private onSendCommitted(): InputEffect[] {
+    this.claim = undefined
+    this.occurrences = []
+    this.adopt('')
+    this.log = []
+    this.redoStack = []
+    this.typingRun = undefined
+    this.paste = undefined
+    return []
+  }
+
   private onRelease(): InputEffect[] {
     if (this.inflight !== undefined) {
       this.inflight.controller.abort()

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

@@ -77,7 +77,11 @@ export function ConversationRoot({
 
   return (
     <div className={css.root} data-phase={hero ? 'hero' : 'active'}>
-      {!hero && renderSlot('conversation.session', {})}
+      {/* Mounted for every real session, hero included: ConversationSession
+          renders no chrome while blank but owns the draft-persistence mirror
+          bind — unmounting it in the hero would lose pre-first-send text on
+          a refresh or scope rebuild. */}
+      {sessionId !== undefined && renderSlot('conversation.session', {})}
       {renderSlotChain(
         'conversation.composer',
         { interactions: pending },