[Feature]: Call external editor in REPL

[Alexx999]

1. Why Do You NEED This Feature?

I really really NEED this feature because:
Multi-line pasting is broken in REPL (at least on Windows) so there's literally no way to paste couple lines from logs/error message/whatever aside from doing it line-by-line

2. What Is NOT Possible Right Now?

Currently, I cannot open EDITOR/FORGE_EDITOR from the REPL environment.
There's :edit but it's for zsh, I haven't been able to find it in the REPL

Workaround:
Paste to a text file and mention it, e.g. "logs are in the log.txt"

3. What WILL Be Possible With This Feature?

Use editor to edit queries in the REPL

Proposed Solution (User Experience)

Have a hotkey (like Claude/Codex Ctrl-G) or an /edit command which will open user's configured text editor with current prompt contents

Alternatives Considered

No response

Feature Category

CLI/UX

Priority/Impact

High - Would significantly improve my workflow

Examples from Other Tools

Ctrl-G in Claude Code or Codex CLI

Additional Context

No response

Pre-submission Checklist

• I have searched existing issues and confirmed this is not a duplicate
• I am willing to submit a PR to implement this feature

[tusharmath]

Fixed in #2984