editor: Add automatic markdown list continuation on newline and indent on tab (#42800)

Closes #5089

Release notes:
- Markdown lists now continue automatically when you press Enter
(unordered, ordered, and task lists). This can be configured with
`extend_list_on_newline` (default: true).
- You can now indent list markers with Tab to quickly create nested
lists. This can be configured with `indent_list_on_tab` (default: true).

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Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Smit Barmase <heysmitbarmase@gmail.com>
a7e07010e5Raduan A. committed on 12/19/2025, 4:14:02 PM· committed by GitHubparentea34cc5
10 files changedLine totals unavailable