Move osrd-ui into main osrd repository

[emersion]

Description and goal

A pain point when working on osrd-ui is that it's tricky to work on osrd-ui and test the changes in OSRD in a real-world scenario instead of a storybook. Additionally, osrd-ui changes are costly: each time we want to update osrd-ui (e.g. for a bugfix or small enhancement) we need to create a new osrd-ui release and then bump the osrd-ui dependency in OSRD's package.json.

We could move osrd-ui into a subdirectory of the main OSRD repository. osrd-ui's NPM packages would continue to work as usual. OSRD's front could pull osrd-ui from a local directory instead of the NPM registry.

Possible roadblocks:

• How do we integrate osrd-ui's multi-package/lerna setup into OSRD's front build process ?
• Do we want to retain git history? (It's possible)
• yarn vs npm?
• Release process? Right now we use git tags, GitHub releases and a GitHub actions workflow.

Acceptance criteria

.

[emersion]

Random notes:

• NPM workspaces
• Use Docker additionalContexts to add osrd-ui's source files in? Alternatively, put osrd-ui inside front/.
• https://vite.dev/guide/dep-pre-bundling.html#monorepos-and-linked-dependencies
• https://v2.vitejs.dev/config/#server-watch

[emersion]

• How to use osrd-ui from osrd?
  • Poor man's monorepo: file: dependencies and cd osrd-ui && npm run build before
  • NPM workspaces
    • Nested workspaces?
    • A single workspace with osrd and ui-* sub-packages? Not sure this will work with our directory layout.
    • A single workspace with osrd as root and ui-* sub-packages?
• How to integrate osrd-ui's build system with osrd's?
  • Good ol' && (con: sequential)
  • run-p
  • lerna
• We probably want some kind of build caching for osrd-ui, otherwise startup will be slow as hell
  • One way is Build in parallel and enable caching #718
  • Another way would be to switch from rollup to vite
• Where to put osrd-ui in the osrd repo?
  • ui/
  • front/ui/
• Release process
  • Synced with osrd?
  • GitHub release with the name "osrd-ui"?
  • Manual