[FIX] hr_{recruitment,skills},mass_mailing,project,note: milk adaptations

hr_recruitment: switch smart button value and label
- Switching applicant's name with "Employee" label to be consistent with
  the rest of smart button's format

mass_mailing: adapt status bar layout
- Removed excessive margin between the status bar and the content
- Added no padding between status bar and the control panel
- Removed a useless border before the status
- Improved margin between alert and buttons

project: right side panel stats buttons alignment

hr_skills: fix `::before` alignment

== ISSUE ==

Before this commit, the :before line in Employee resume is not aligned
with the dots. This is due to the fact that the variable
$o-hrs-timeline-entry-padding used in the mixin isn't the right value we
should use.

There was also an issue with responsive.

== After this commit ==

We now use a calc, which process the half of the circle plus the padding
minus the border-width. The $o-horizontal-padding is the variable used
to define the padding of the line inside the form view.

We adapt this in a smaller media query since the $o-horizontal-padding
value is different.

task-2818586

Part-of: odoo/odoo#116641

addons/note/static/src/scss/note.scss

@@ -7,7 +7,6 @@
     .o_form_sheet_bg {
         display: flex;
         flex-direction: column;
-        padding: 0;
         .o_form_statusbar {
             margin: 0;
         }