Speed up development builds

CATcher builds can take quite long (up to 25s).
We can consider changing some configurations for `ng build` to increase the compile times, in development mode only.
some options to investigate: [here](https://stackoverflow.com/a/68209567)

Not a priority since the incremental build time is ~1s. Although faster will be nicer.

Start by locating the Angular `ng build` configuration and comparing development-mode options with the linked Stack Overflow suggestions. Measure a clean development build, then verify that the configuration reduces its time without changing incremental builds or production behavior.

Written by the indexing model from the issue text.