feat: display current version in footer

[NicolasIRAGNE]

useful for both production and development (sometimes im wondering if my commit has been properly deployed to PR env and stuff)

im thinking the priorities should be in order

1. if there's a tag, use that (so eg v0.2.0)
2. if we're on a commit, short hash
3. (optional) if we're on a commit with git diff changes, <short hash>-dirty