feat: scope + un-bundle the plugin; @unom/ui SPA; custom-emulator editor

Reliability + correctness pass on the packaging and UI.

Packaging — drop the self-contained bundle:
- Rename to `@punktfunk/plugin-rom-manager` (scoped). An unscoped package can't
  be split across registries, which is the only reason bundling effect + the SDK
  into every plugin seemed necessary. Scoped names resolve from one scope-map, so
  the plugin depends on `@punktfunk/host` + `effect` as SHARED (hoisted) deps —
  no duplication, no ~1 MB effect copy per plugin. Build is back to plain `tsc`.
  (Runner-side discovery of `@punktfunk/plugin-*` shipped in @punktfunk/host 0.1.1.)

UI — use the console's design system so it reads as family:
- SPA rebuilt on @unom/style tokens + Tailwind v4 + the console's exact theme
  (violet chrome, Geist, card/button vocabulary). Build-time only → static assets
  in dist/ui, no @unom runtime dep. Skips @unom/ui's AnimatedButton/Card, which
  statically import ~7 MB of UI sound assets — same look, 416 KB dist/ui.
- Add a custom-emulator editor (Emulators page) writing config.emulators — you can
  now add a launcher Punktfunk doesn't ship a definition for.
- Fix brand capitalization to "Punktfunk" in all UI copy + docs.

Install docs + CI updated for the scoped `bun add @punktfunk/plugin-rom-manager`
flow. 48 engine tests green; backend + UI typecheck + biome clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

ui/bunfig.toml

@@ -0,0 +1,6 @@
+# The @unom design-system packages (@unom/ui, @unom/style) live on the Gitea registry. Auth comes
+# from your ~/.npmrc (`//git.unom.io/api/packages/unom/npm/:_authToken`); CI needs the same token as a
+# secret. These are BUILD-time only — the SPA compiles to static assets in ../dist/ui, so the published
+# plugin has no @unom runtime dependency.
+[install.scopes]
+"@unom" = "https://git.unom.io/api/packages/unom/npm/"