Migrate frontend to Svelte 5 #12515
Description
In a recent crates.io team meeting, we decided to explore Svelte 5 as a replacement for our Ember.js frontend. We evaluated several options including server-side rendering via Rust (e.g., with minijinja) and concluded that Svelte is currently our best option, primarily for developer experience reasons given our small team size.
Rather than a big-bang rewrite, we're taking an incremental approach. The new Svelte app lives in the /svelte/ directory and is served at /svelte/ alongside the existing Ember.js app. This allows us to migrate components and routes one at a time, keeping each PR reviewable. Once the Svelte app reaches feature parity with the Ember.js app, we'll swap it to be the primary frontend.
The Svelte app is a work in progress and not yet production-ready. Review feedback on architecture and patterns is welcome as we establish conventions.
This issue serves as a tracking issue for the migration. Related pull requests should reference it to provide context.