Fork assistant turns into new drafts (#1788)

* feat(chat): fork assistant turns into new drafts

Builds chat-history attachments on the daemon and routes them into draft composers so users can continue an assistant turn in an existing workspace tab or New Workspace.

* fix(chat): clean up fork draft handling

* fix(chat): address fork draft review feedback

* fix(server): build fork context from bounded timeline

* fix(app): restore assistant turn footer in streams

* fix(app): preserve fork draft setup

* fix(app): tighten assistant fork footers

* fix(app): lock active fork draft handoff

* fix(app): preserve attachment-only draft retries

* fix(app): unify composer attachment scopes

* fix(app): align chat history attachment labels

* fix(app): centralize attachment pill content

* fix(app): trim fork context for workspace naming

packages/app/src/stores/create-flow-store.ts

@@ -17,6 +17,20 @@ export interface PendingCreateAttempt {
   attachments?: AgentAttachment[];
 }
 
+export function isActiveCreateFlowForDraft(input: {
+  pending: PendingCreateAttempt | null | undefined;
+  serverId: string;
+  draftId: string | null | undefined;
+}): boolean {
+  const draftId = input.draftId?.trim();
+  return Boolean(
+    draftId &&
+    input.pending?.draftId === draftId &&
+    input.pending.serverId === input.serverId &&
+    input.pending.lifecycle === "active",
+  );
+}
+
 interface CreateFlowState {
   pendingByDraftId: Record<string, PendingCreateAttempt>;
   setPending: (pending: Omit<PendingCreateAttempt, "lifecycle">) => void;