Demo Work

[iamseeley]

This PR includes:

1. Disabled cmd+shift+l - commented out keybinding for "Select
   All Occurrences" in multicursor.ts
2. Orange text selection - editor.selectionBackground: #ff800033
   in both Membrane themes
3. Orange hover highlight - editor.hoverHighlightBackground:
   #ff800033 in both Membrane themes
4. Orange word highlight - editor.wordHighlightBackground and
   editor.wordHighlightStrongBackground in both Membrane themes
5. Hover stays in editor bounds - allowEditorOverflow = false in
   resizableContentWidget.ts + clamped aboveTop to Math.max(0,
   ...) in contentWidgets.ts