Add Ctrl+U shortcut

[nuckle]

Description

Closes this issue - #1689

Screenshots

Before pressing Ctrl+U

After pressing Ctrl+U

Additional information

This shortcut needs to be listed here - https://github.com/JustArchiNET/ASF-ui/wiki/Features#shortcuts

Checklist

• My pull request is not a duplicate
• I added a descriptive title to this pull request
• I added a concise description or a self-explanatory screenshot to this pull request
• My code follows the code style of this project
• I have performed a self-review of my own code

[Aareksio]

If nextTick works here, I'd use it instead of setTimeout

[nuckle]

Like so?

      jumpToStart() {
        const el = this.$refs['terminal-input'];
        if (el.setSelectionRange) el.setSelectionRange(0, 0);
      },

      deleteBeforeCursorAndJumpToStart() {
        this.removeBeforeCursor();
        this.$nextTick(() => {
          this.jumpToStart();
        })
      },

[Aareksio]

I'd just replace setTimeout with next tick:

if (el.setSelectionRange) {
  this.$nextTick(() => el.setSelectionRange(0, 0));
}

I do not know why you require setTimeout in the first place, but nextTick should achieve similar result

[nuckle]

I'm not sure about this too, but it's required in this case to use setTimeout or nextTick. I decided to use setTimeout, because there's a similar function moveCursorToEnd that uses this. But I agree that nextTrick is a better choice

moveCursorToEnd() {
  const el = this.$refs['terminal-input'];
  const len = this.command.length;

  if (el.setSelectionRange) setTimeout(() => el.setSelectionRange(len, len), 0);
}

[Aareksio]

Ah right, you followed the pattern. This is good. @MrBurrBurr merge? Apart from fulfilling Botan's request, this looks solid and harmless.

[MrBurrBurr]

I will take a look and see why we are using setTimeout and if we need it or if it could be replaced with nextTick.

Other than that, thank you @nuckle for your contribution - LGTM!