refactor: Overhaul Plugin Architecture & Playground UI (#1846)

* refactor: Move Plugins Out and Consolidate with Multisrc

* feat: Overhaul Playground UI

* feat: Add Filters to New UI

* feat: Persist Selected Plugin

* feat: Add Direct Parse Novel/Chapter Options and Feedback Toasts

[skip ci]

* feat: UX Improvements

* chore: Update Plugin Path in Publish Workflow

* fix: Add Backward Compatibility

* chore: Update Plugin Publishing Script

src/components/ui/skeleton.tsx

@@ -0,0 +1,16 @@
+import * as React from 'react';
+import { cn } from '@/lib/utils';
+
+function Skeleton({
+  className,
+  ...props
+}: React.HTMLAttributes<HTMLDivElement>) {
+  return (
+    <div
+      className={cn('animate-pulse rounded-md bg-muted/50', className)}
+      {...props}
+    />
+  );
+}
+
+export { Skeleton };