Reduce Total Bundle Size

### Description

Total bundle size is one of the most important factors in time to first paint for a SPA.

Today, the JS bundle alone is over 2MB when built, made up of:

- vendors.js (1 MB)
- main.js (602.76 KB)
- set up.js (589.28 KB)
- runtime.js (1.69 KB)

Ideally, these files should be < 244 KiB

There are some quick wins in FlowForges dependencies that will reduce the bundle size at low dev effort:

- [ ] Remove Moment.js and replace with a modern alternative such as Day.js
- [ ] Ensure tree shaking is working for @heroicons/vue to only import used icons

Other targets that might be more involved:

- [ ] Duplication between main.js and setup.js
- [ ] Splitting into sub-bundles

### Epic/Story

_No response_