In case the saved "selected languages" contained languages that did not have any installed source, they caused TypeErrors when trying to access them in e.g. "sourcesByLanguage".
Switch to "lingui" for better DX.
Tried to persist existing languages as much as possible.
Removed "vite-plugin-node-polyfills" because it's incompatible with "lingui"
The server is not requesting these images through an extension; thus, it is not a problem to send them directly to the server since there is no problem of getting the server "stuck" due to extension rate limits.
The loading placeholder was never removed in case the whole source catalogue was added to the library and the "hide entries in library" setting has been enabled.
