323 Application Load Buffering and Backend Search

[bodhiYG]

ℹ️ Issue

Closes

📝 Description

Write a short summary of what you added. Why is it important? Any member of C4C should be able to read this and understand your contribution -- not just your team members.

Briefly list the changes made to the code:

Backend

1. Added pagination: findAll and findByDisciplines now return a PaginatedResult (data/total/page/limit) instead of full arrays
2. Added column projection: list endpoints select only the 8 fields the table renders (APPLICATION_LIST_COLUMNS), dropping the bulk of each row
3. Added a query DTO (ApplicationQueryDto) for page/limit, plus server-side search, statuses, and date-range filters; enabled transform: true on the global validation pipe
4. Added server-side search across all searchable columns (incl. off-table fields) via a QueryBuilder ILIKE OR-group, with statuses IN (...) and inclusive date bounds
5. Added DB indexes on email, discipline, appStatus (entity decorators + migration)

Frontend:

1. API client + types now send/consume the paginated shape and list params (PaginatedResponse, ApplicationListParams).
2. useApplications refactored to fetch one page server-side: debouncedsearch, discipline/admin-name filters resolved to discipline keys, complete (non-page-limited) filter options exposed
3. ApplicationTable reduced to a presentational component (client-side search/filter removed)
4. AdminLanding wires its search/filter state into the hook, uses real page counts, and resets to page 1 on search/filter change

✔️ Verification

What steps did you take to verify your changes work? These should be clear enough for someone to be able to clone the branch and follow the steps themselves.

Tests

1. Updated backend service/controller specs for the paginated shapes and added findByDisciplines search/filter tests
2. Updated frontend hook/page tests for the new signatures; trimmed ApplicationTable tests to presentational only

Provide screenshots of any new components, styling changes, or pages.

🏕️ (Optional) Future Work / Notes

Did you notice anything ugly during the course of this ticket? Any bugs, design challenges, or unexpected behavior? Write it down so we can clean it up in a future ticket!

[SamNie2027]

did yarn db:reset-and-seed: Tried a basic search and I get

[Nest] 60072  - 06/17/2026, 8:59:30 PM   ERROR [TypeOrmExceptionFilter] Unhandled QueryFailedError

QueryFailedError: column app.appstatus does not exist
    at PostgresQueryRunner.query (C:\Users\School\Github\proj-bhchp\node_modules\typeorm\src\driver\postgres\PostgresQueryRunner.ts:325:19)
    at processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async SelectQueryBuilder.loadRawResults (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:3868:25)
    at async SelectQueryBuilder.executeEntitiesAndRawResults (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:3614:26)
    at async SelectQueryBuilder.getManyAndCount (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:1874:36)
    at async ApplicationsService.findByDisciplines (webpack:///./src/applications/applications.service.ts:551:27)
    at async ApplicationsController.getApplicationsByDisciplines (webpack:///./src/applications/applications.controller.ts:153:12)

Please do more manual testing as I didn't see you mention manual testing in your "verification" section of your PR

[SamNie2027]

Same with the filter

[Nest] 60072  - 06/17/2026, 9:01:33 PM   ERROR [TypeOrmExceptionFilter] Unhandled QueryFailedError
QueryFailedError: column app.proposedstartdate does not exist
    at PostgresQueryRunner.query (C:\Users\School\Github\proj-bhchp\node_modules\typeorm\src\driver\postgres\PostgresQueryRunner.ts:325:19)
    at processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async SelectQueryBuilder.loadRawResults (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:3868:25)
    at async SelectQueryBuilder.executeEntitiesAndRawResults (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:3614:26)
    at async SelectQueryBuilder.getManyAndCount (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:1874:36)
    at async ApplicationsService.findByDisciplines (webpack:///./src/applications/applications.service.ts:551:27)
    at async ApplicationsController.getApplicationsByDisciplines (webpack:///./src/applications/applications.controller.ts:153:12)

[Nest] 60072  - 06/17/2026, 9:01:35 PM   DEBUG [JwtStrategy] Validated JWT payload: sub=11abd550-d061-70ce-53ac-3d3a98b94d3e, token_use=id
[Nest] 60072  - 06/17/2026, 9:01:35 PM   ERROR [TypeOrmExceptionFilter] Unhandled QueryFailedError
QueryFailedError: column app.proposedstartdate does not exist
    at PostgresQueryRunner.query (C:\Users\School\Github\proj-bhchp\node_modules\typeorm\src\driver\postgres\PostgresQueryRunner.ts:325:19)
    at processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async SelectQueryBuilder.loadRawResults (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:3868:25)
    at async SelectQueryBuilder.executeEntitiesAndRawResults (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:3614:26)
    at async SelectQueryBuilder.getManyAndCount (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:1874:36)
    at async ApplicationsService.findByDisciplines (webpack:///./src/applications/applications.service.ts:551:27)
    at async ApplicationsController.getApplicationsByDisciplines (webpack:///./src/applications/applications.controller.ts:153:12)

[Nest] 60072  - 06/17/2026, 9:01:35 PM   DEBUG [JwtStrategy] Validated JWT payload: sub=11abd550-d061-70ce-53ac-3d3a98b94d3e, token_use=id
[Nest] 60072  - 06/17/2026, 9:01:35 PM   ERROR [TypeOrmExceptionFilter] Unhandled QueryFailedError

QueryFailedError: column app.proposedstartdate does not exist
    at PostgresQueryRunner.query (C:\Users\School\Github\proj-bhchp\node_modules\typeorm\src\driver\postgres\PostgresQueryRunner.ts:325:19)
    at processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async SelectQueryBuilder.loadRawResults (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:3868:25)
    at async SelectQueryBuilder.executeEntitiesAndRawResults (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:3614:26)
    at async SelectQueryBuilder.getManyAndCount (C:\Users\School\Github\proj-bhchp\node_modules\src\query-builder\SelectQueryBuilder.ts:1874:36)
    at async ApplicationsService.findByDisciplines (webpack:///./src/applications/applications.service.ts:551:27)
    at async ApplicationsController.getApplicationsByDisciplines (webpack:///./src/applications/applications.controller.ts:153:12)

[SamNie2027]

Adding the structured filters into this is an interesting choice but I guess the structured filters are so specific its fine

[SamNie2027]

Could perhaps explore adding an "Apply" button to the search or using the "Apply" for in the filters instead of the debounce