This commit fixes the recently converted color_picker field
widget. It is now always opened in a list as in legacy,
no longer togglable and many style issues have been fixed.
In form views, we still toggle the opened state because
always edit is coming and it would bloat the UI to
keep it always open.
Tests has been added/modified to assert those desired
behaviors.
closesodoo/odoo#97872
Signed-off-by: Simon Genin (ges@odoo) <ges@odoo.com>