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/attachments/workspace-attachment-utils.ts

@@ -22,6 +22,7 @@ export function isWorkspaceAttachment(
   return (
     attachment?.kind === "review" ||
     attachment?.kind === "browser_element" ||
+    attachment?.kind === "chat_history" ||
     isPullRequestContextAttachment(attachment)
   );
 }
@@ -33,6 +34,7 @@ export function userAttachmentsOnly(
     (attachment): attachment is UserComposerAttachment =>
       attachment.kind !== "review" &&
       attachment.kind !== "browser_element" &&
+      attachment.kind !== "chat_history" &&
       !isPullRequestContextAttachment(attachment),
   );
 }
@@ -56,5 +58,8 @@ export function workspaceAttachmentToSubmitAttachment(
       text: attachment.text,
     };
   }
+  if (attachment.kind === "chat_history") {
+    return attachment.attachment;
+  }
   return attachment.kind === "review" ? attachment.attachment : null;
 }