SCSS (or SASS, the client has expressed no preference and both work with Angular)
L3/L4 Experience
Yes responsive design, as some of the screens will be used by personnel in the field on a Samsung tablet (for which we have the specs) in addition to a desktop
Familiarity with ag-grid-enterprise, bootstrap, and ng-bootstrap
No major performance tuning capabilities
No progressive web application
No definition of APIs; consume only (We providing the backend endpoints and all backend local dev environment setup)