Replace kebab menu with headless UI

[cstns]

Description

Replace the kebab menu to use the headless ui menu and align with the rest of headless ui components usage instead of the bespoke collision detection.

I had to alter some e2e tests that were relying on a double click in order to open the menu, in that i remove the 2nd click because it was not correctly causing the kebab menu to close.

Also had to alter the ListItem unit test to properly test the headless ui component.

Related Issue(s)

part of #6374

Checklist

• I have read the contribution guidelines
• Suitable unit/system level tests have been added and they pass
• Documentation has been updated
  • Upgrade instructions
  • Configuration details
  • Concepts
• Changes flowforge.yml?
  • Issue/PR raised on FlowFuse/helm to update ConfigMap Template
  • Issue/PR raised on FlowFuse/CloudProject to update values for Staging/Production
• Link to Changelog Entry PR, or note why one is not needed.

Labels

• Includes a DB migration? -> add the area:migration label

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.42%. Comparing base (cef540c) to head (eda8500).

Additional details and impacted files

@@                     Coverage Diff                     @@
##           teleported-menus-alignment    #6489   +/-   ##
===========================================================
  Coverage                       76.42%   76.42%           
===========================================================
  Files                             396      396           
  Lines                           19885    19885           
  Branches                         4766     4766           
===========================================================
  Hits                            15198    15198           
  Misses                           4687     4687           

Flag	Coverage Δ
backend	76.42% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.