Fix instance creation form getting stuck without a team after refresh

[cstns]

Description

Extended the loading screen state to include the time it takes to load the teams.

The issue was caused by a combination of factors:

• we are passing the team from the createInstance.vue page down to the InstanceForm
• there is no persistent state for teams in local storage and each full page refresh needs to call all API endpoints again
• creation form also loads teams

There is a short moment after the page re-loads and the team call is not finalized but the InstanceForm gets mounted with a null team prop and fails it's created method's api calls due to the team being null.

Related Issue(s)

part of #3884
closes #3934

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

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 79.28%. Comparing base (d319e0d) to head (7163e5d).
Report is 8 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3945   +/-   ##
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  Coverage   79.28%   79.28%           
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  Files         281      281           
  Lines       12755    12755           
  Branches     2844     2844           
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  Hits        10113    10113           
  Misses       2642     2642           

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