Feature request: import/merge a side-chat session into the main session (like Cursor's side chat)

Cursor has a workflow where you can open a side chat, have a discussion there, and explicitly import that conversation's content into your main chat session so the main session becomes aware of it.

Claude Code doesn't have an equivalent. The closest options are:

• search_session_transcripts (via MCP) — requires manually searching and pasting, not a one-click import
• /fork — branches a session outward, not merging one back in
• Session resume — continues an old session, doesn't merge into a currently-open one

Would love a native way to pull another session's content/context into the currently active session.