In text editor, fix behaviour of Home and End keys

[alexjpwalker]

Usage and product changes

The behaviour of Home and End keys are now in line with most other text editors, moving to the start/end of the line (rather than the file) unless Ctrl (Cmd on MacOS) is additionally pressed.

Implementation

We had some confusing terminology in the Command class - MOVE_HOME and MOVE_END intuitively sounded like they should correspond to a keyboard's Home and End keys, but this resulted in incorrect behaviour. We've renamed them to MOVE_CONTENT_START and MOVE_CONTENT_END, and these are now correctly only triggered by Ctrl+Home and Ctrl+End respectively. Home and End take you to the start/end of a line. If Shift is additionally pressed in any case, trigger selection.

[typedb-bot]

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Trivial Change

• This change is trivial and does not require a code or architecture review.

Code

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[alexjpwalker]

NB this is the correct fix to

• Shift+End selects to end of file, not end of line #555