[REFACTOR] Fetch BPMN diagrams in projects instead of bundling them with the JS code

[tbouffard]

Currently. the BPMN diagrams are stored as string within the JS bundles. This increases the size of the bundle and does not reflect what an application generally does: it doesn't store the diagrams that are retrieved from services or API. This also applies to the upcoming "Vue" example: #501

See also https://github.com/process-analytics/bpmn-visualization-examples/issues/18#issuecomment-1136188676

⚠️ Warning: remember that the "projects" are often deployed in non root context. This can impact the way diagrams are fetched. See https://github.com/process-analytics/bpmn-visualization-examples/pull/501/files/c764eb211ac34014b1091874635ae22b73c84741#diff-538d08d2ccf3dd8a78b49e615961ebd25870ba4e727a2848fd645d8a80f0cd66

Notes

We also have the same need for demo built in other repositories

• https://github.com/process-analytics/bv-experimental-add-ons/issues/72
• https://github.com/process-analytics/bpmn-visualization-demo-template/issues/20
• https://github.com/process-analytics/bonita-day-demo-2023/issues/110
• https://process-analytics.github.io/icpm-demo-2022/

### Projects to update
- [ ] angular
- [ ] lit-element
- [ ] parcel
- [ ] rsbuild: #601
- [ ] rollup
- [ ] vitejs
- [ ] vue
- [ ] webpack