This PR essentially refactors some hard-coded values for width and
height in the table.
It also fixes a few differences from the Figma design, on the checkbox
column width and the top bar and view bar left alignment with the table.
The blue color has been set like before the refactor of the focus portal
(`theme.adaptiveColors.blue4`)
Fixes in https://github.com/twentyhq/core-team-issues/issues/1490 :
- Fix first drag and drop column width that has changed from main (see
Figma)
- Unify all widths, heights, z-index, etc. with constants
- Put same blue as before for focused portal
Also removed `focus-active` class because we now use a portal for the
focus.
