[Renaming-Front] Source -> Project

[BPierrick]

Fixes

• Issue incoming

Description

• Changed source & sourceId variable names
• Updated route URLs and search param namings
• Renamed files with source in their name
• Changed components/slices/types containing source names
• Updated en.json translations
• Updated README.md
• Updated unit tests

Definition of Done

• [ ] I followed the Arkhn Code Book (I swear!).
• [ ] I have written tests for the code I added or updated.
• [ ] I have updated the documentation according to my changes.
• [ ] I have updated the deployment configuration if needed.

[simonvadee]

temporarily(?) deprioritized