Fleet UI: Fix user management page overflow

[RachelElysia]

Issue

For #25015

Description

• Fix user management page overflowing for currently supported screens by hiding columns and setting max width to columns when overflowing
• Add responsiveness to table and table headers down to 320
  • NOTE: A more global approach to table header responsiveness designs is ideal for maintainability and scalability and will require a refactor
• Other part of this ticket: Fix empty integration container from overflowing page down to 768px

Other

• Refactor to global fix to replace all locally hidden header cell left border to not display for view all host/action column (Note: this was added because hiding columns would make the current "border-right: none on whatever's the second to last column" really annoying and much easier to just say border-left: none of those action/view all host header)

Screenrecording of fix / Screenshot of improvement

Screen.Recording.2025-01-23.at.2.42.01.PM.mov

Checklist for submitter

If some of the following don't apply, delete the relevant line.

• Changes file added for user-visible changes in changes/, orbit/changes/ or ee/fleetd-chrome/changes.
• A detailed QA plan exists on the associated ticket (if it isn't there, work with the product group's QA engineer to add it)
• Manual QA for all new/changed functionality

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.61%. Comparing base (d893025) to head (3f28b3f).
Report is 14 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #25733   +/-   ##
=======================================
  Coverage   63.61%   63.61%           
=======================================
  Files        1624     1624           
  Lines      155309   155309           
  Branches     4003     4054   +51     
=======================================
  Hits        98797    98797           
  Misses      48714    48714           
  Partials     7798     7798           

Flag	Coverage Δ
frontend	53.08% <ø> (ø)

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[iansltx]

Couple quick Q's. Main thing is making sure that all changes are documented so they can get QA'd.

[iansltx]

LGTM