Add loading status to site settings data related dropdown

[erinz2020]

in some environments, the site-settings response can be slow, causing certain dropdowns to briefly render with empty options. this PR adds loading spinners to the affected selects on the Encounter and Search Encounter pages to clearly indicate the options are still loading and avoid confusion

PR fixes #1443

[codecov-commenter]

Codecov Report

❌ Patch coverage is 52.98013% with 71 lines in your changes missing coverage. Please review.
✅ Project coverage is 46.91%. Comparing base (5dcae11) to head (78b54cc).

Files with missing lines	Patch %	Lines
frontend/src/pages/Encounter/MatchCriteria.jsx	37.50%	18 Missing and 2 partials ⚠️
...ntend/src/components/filterFields/SocialFilter.jsx	57.14%	9 Missing ⚠️
frontend/src/pages/Encounter/ProjectsCard.jsx	12.50%	7 Missing ⚠️
...tend/src/pages/Encounter/AttributesSectionEdit.jsx	73.91%	6 Missing ⚠️
frontend/src/pages/Encounter/Encounter.jsx	45.45%	6 Missing ⚠️
...d/src/components/filterFields/ImageLabelFilter.jsx	54.54%	5 Missing ⚠️
...ntend/src/pages/Encounter/stores/EncounterStore.js	20.00%	4 Missing ⚠️
...src/pages/SearchPages/stores/EncounterFormStore.js	20.00%	4 Missing ⚠️
frontend/src/components/ContainerWithSpinner.jsx	66.66%	1 Missing and 1 partial ⚠️
frontend/src/components/DataTable.jsx	0.00%	2 Missing ⚠️
... and 4 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1446      +/-   ##
==========================================
- Coverage   47.21%   46.91%   -0.30%     
==========================================
  Files         272      274       +2     
  Lines        9720     9783      +63     
  Branches     2862     2895      +33     
==========================================
+ Hits         4589     4590       +1     
- Misses       4900     4959      +59     
- Partials      231      234       +3     

Flag	Coverage Δ
backend	46.91% <52.98%> (-0.30%)	⬇️
frontend	46.91% <52.98%> (-0.30%)	⬇️

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[vkirkl]

Do we know why the site-settings response is slow? Can we address that as well?

[JasonWildMe]

LGTM

[erinz2020]

Do we know why the site-settings response is slow? Can we address that as well?

it might be related to both frontend and backend. in another branch I have some updates on reducing calls of site-settings, once that got merged, I'll updated related pages to use context provider instead of making new calls every page