[FEATURE]: Select all current text

[perinst]

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

Uses Ctrl+Shift+A instead of Ctrl+A because Ctrl+A is already mapped to "move to start of line" (input_line_home)

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• [FEATURE]: Text selection and navigation inside input with keyboard #3370: [FEATURE]: Text selection and navigation inside input with keyboard - discusses broader keyboard selection functionality
• feat: add keyboard-based copy/cut for input field selection #7516: feat: add keyboard-based copy/cut for input field selection - related keyboard selection enhancements

For keybind-related issues, please also check our pinned keybinds documentation: #4997

Feel free to ignore if none of these address your specific case.

[Simplereally]

Blows my mind how there is no 'highlight all text' keybinding. Please add asap!