fix: various validation related issues (resolves #1776, #1775, #1774, #1773, #1772)

[jobara]

Resolves #1776
Resolves #1775
Resolves #1774
Resolves #1773
Resolves #1772

Additional Changes

• Adds IdentityType enum
• Adds LocationType enum
• Adds validation tests (See Write tests for validation errors  #1813) for some of the request types
• Addresses some runtime errors when invalid data passed to request
• Updates validation error messages
• Corrects some validation rules

Prerequisites

If this PR changes PHP code or dependencies:

• I've run composer format and fixed any code formatting issues.
• I've run composer analyze and addressed any static analysis issues.
• I've run php artisan test and ensured that all tests pass.
• I've run composer localize to update localization source files and committed any changes.

If this PR changes CSS or JavaScript code or dependencies:

• I've run npm run lint and fixed any linting issues.
• I've run npm run build and ensured that CSS and JavaScript assets can be compiled.

[codecov]

Codecov Report

Merging #1820 (b8c7f7a) into dev (6dc89fe) will increase coverage by 0.04%.
The diff coverage is 100.00%.

❗ Current head b8c7f7a differs from pull request most recent head a7f7662. Consider uploading reports for the commit a7f7662 to get more accurate results

@@             Coverage Diff              @@
##                dev    #1820      +/-   ##
============================================
+ Coverage     96.47%   96.52%   +0.04%     
- Complexity     1984     2032      +48     
============================================
  Files           299      301       +2     
  Lines          8636     8746     +110     
============================================
+ Hits           8332     8442     +110     
  Misses          304      304              

Impacted Files	Coverage Δ
app/Enums/IdentityType.php	100.00% <100.00%> (ø)
app/Enums/LocationType.php	100.00% <100.00%> (ø)
app/Http/Controllers/EngagementController.php	100.00% <100.00%> (ø)
app/Http/Requests/AddNotificationableRequest.php	100.00% <100.00%> (ø)
app/Http/Requests/AddTranslationRequest.php	100.00% <100.00%> (ø)
app/Http/Requests/DestroyTranslationRequest.php	100.00% <100.00%> (ø)
app/Http/Requests/MeetingRequest.php	100.00% <100.00%> (ø)
...pp/Http/Requests/RemoveNotificationableRequest.php	100.00% <100.00%> (ø)
app/Http/Requests/SaveIndividualRolesRequest.php	100.00% <100.00%> (ø)
app/Http/Requests/StoreInvitationRequest.php	100.00% <100.00%> (ø)
... and 4 more

[greatislander]

Assuming the tests pass, I think this is ready to merge!