Pranav - fix(backend): create donut chart for applicant experience breakdown

[pranavgovi]

Description

Related PRS (if any):

This is related to PR#3840

Main changes explained:

• Updated jobApplicants model
• Updated app.js to include applicants route
• Updated applicant analytics controller
  …

How to test:

1. check into current branch
2. do npm install and ... to run this PR locally
3. Clear site data/cache
4. log as admin user
5. go to postman and obtain a valid token by sending a POST request to http://localhost:4500/api/login
6. Use the token and send a GET request to http://localhost:4500/api/applicants/experience-breakdown to obtain the breakdown of applicants based on experience.
7. Also test it by sending start date and end date params like http://localhost:4500/api/applicants/experience-breakdown?startDate=2020-01-01&endDate=2025-01-01

Screenshots or videos of changes:

Note:

This backend PR needs some work regarding filtering by role. So don't test it for now. Front end also should be completed by next week.

[csk731]

The changes look good to me, and the API response is working as expected.

Also, when the startDate is greater than the endDate, the response is empty, which is a good edge case handling.

[suparshwa31]

I tested the changes and both the api endpoints are working great.

[sirisudheeksha]

Tested the changes locally both the API endpoints are working as expected and returning correct experience breakdown data.

[beblicarl]

Reviewed the frontend and everything worked as intended and the code is great

OneCommunityGlobal/HighestGoodNetworkApp#3840 (comment)