More validation and code quality enhancements for bulk invites

Added check for null data
Added check for duplicate data in Supabase instead of just locally
Switched from ForEach loop to for loop to allow for early returns when encountering an error

[x] Bug fix (non-breaking change which fixes an issue)
[ ] Issue fix (non-breaking change that addresses existing opened issue)
[x] New feature (non-breaking change which adds functionality)
[ ] Breaking change (fix or feature that would cause existing functionality to change)
[ ] Refactoring change (refactoring change must not apply any form of functional change)

N/A

N/A

[x] Related issues linked using fixes #number. / There is no issue fix.
[x] Unit tests or E2E tests added for any new feature changes. / There is no new feature that requires test.
[x] Ensured that there's no linter errors.
[x] Ran the full set of testings and coverage reports exceed 80%. / There is currently no test.
[x] All Merge Conflicts have been fully resolved.
[x] Branch is rebased off the target branch.
[x] This PR is complete and does not have incomplete work that'll break the application.

kKar1503 / project-inc-siwma-1