Milestone, incl. support for HMR in Svelte 4's new custom elements im…

…plementation (see sveltejs/svelte#8681 and sveltejs/svelte#8457)

README.md

@@ -85,7 +85,15 @@ On the immediate horizon:
 - [ ] ⏳ Better support for slots during early execution of IIFE compiled packages, i.e. use `MutationObserver` to watch
 	for light DOM slots during initial parsing (see https://github.com/patricknelson/svelte-retag/issues/7)
 - [ ] Support Lit-style lowercase props (see https://github.com/crisward/svelte-tag/issues/16)
-- [ ] Support context (see https://github.com/crisward/svelte-tag/issues/8)
+- [ ] Lower priority: Support context (see https://github.com/crisward/svelte-tag/issues/8)
+
+Milestones:
+
+- **v1:** WIP ⏳ (see TODO's above)
+- **v2:** Svelte 4 support. i.e. Add HMR to Svelte 4's custom elements implementation, utilize exactly the same syntax
+	as `<svelte:options customElements={...} />` ([documentation](https://github.com/sveltejs/svelte/blob/version-4/site/content/docs/04-run-time.md#custom-element-api),
+	see also https://github.com/sveltejs/svelte/pull/8681
+	and https://github.com/sveltejs/svelte/issues/8457)
 
 ## Support & Contribution