repl: add possibility to edit multiline commands while adding them

[puskin94]

Summary

This PR builds upon the multiline editing support added to the REPL history in #57400, enhancing it with the ability to edit multiline input as you're writing it, before it even reaches the history.

Key Features

1. Inline Multiline Editing: You can now insert, delete, edit, and split lines while composing a REPL command. This brings a more fluid editing experience, similar to what you'd expect from a basic code editor. See the GIF below for a demo.

2. TTY-only Support: This feature makes heavy use of cursor movement to efficiently draw and clear parts of the current input. As a result, it currently only works in TTY environments.

3. Unchanged Execution Behavior: Pressing Enter behaves as usual:

   • If the current input is a complete and valid command, it executes.
   • If not, a new line is added, continuing multiline input.

4. Limitations:

   • If you want to insert a new line in the middle of a complete multiline command, you’ll need to first make the command incomplete (e.g. by removing a closing } or `).
   • The logic for inserting new lines in complete commands is in place, but I ran into trouble capturing a reliable shortcut like Shift + Enter. I’ve left a TODO to revisit this and debug further.

[codecov]

Codecov Report

Attention: Patch coverage is 98.79518% with 2 lines in your changes missing coverage. Please review.

Project coverage is 90.27%. Comparing base (c11c7be) to head (1947902).
Report is 50 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/internal/readline/interface.js	98.72%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #58003      +/-   ##
==========================================
+ Coverage   90.24%   90.27%   +0.03%     
==========================================
  Files         630      630              
  Lines      185788   186279     +491     
  Branches    36429    36493      +64     
==========================================
+ Hits       167659   168169     +510     
+ Misses      11004    10982      -22     
- Partials     7125     7128       +3     

Files with missing lines	Coverage Δ
lib/repl.js	94.98% <100.00%> (-0.05%)	⬇️
lib/internal/readline/interface.js	96.84% <98.72%> (+0.04%)	⬆️

... and 62 files with indirect coverage changes

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