Syntax highlighting in PyREPL

[ambv]

We want PyREPL to syntax highlight Python code, like this:

Theming support is planned, but a separate concern. This issue is about enabling syntax to highlight correctly whenever color is used within the REPL anyway.

This is a feature for 3.14, with some test and code refactors that we will be bringing back to 3.13 for improved future maintenance.

Linked PRs

• gh-131507: Clean up tests and type checking for _pyrepl #131509
• [3.13] gh-131507: Clean up tests and type checking for _pyrepl (GH-131509) #131546
• gh-131507: Refactor screen and cursor position calculations #131547
• [3.13] gh-131507: Refactor screen and cursor position calculations (GH-131547) #131557
• gh-131507: Add support for syntax highlighting in PyREPL #131562
• gh-131507: Remove Misc/mypy symlinks from the repository #132270
• gh-131507: Add a way to recreate the Misc/mypy symlinks if missing #132274
• [3.13] gh-131507: Add a way to recreate the Misc/mypy symlinks if missing (GH-132274) #132293
• gh-131507: Add support for syntax highlighting in PyREPL #133247