refactor: align article author with VideoModel, streamline selects, fix flyout inert

- Remove ArticleAuthor type; article.author now reuses VideoModel (id, artist_name, slug, avatar)
- updateArticle accepts authorId; author selectable in admin article edit page
- Article edit: single Select with bind:value + $derived selectedAuthor display
- Video edit: replace pill toggles with Select type="multiple" bind:value for models
- Video table: replace inline badge spans with Badge component
- Magazine: display artist_name throughout, author bio links to model profile
- Fix flyout aria-hidden warning: replace with inert attribute

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/types/src/index.ts

@@ -87,14 +87,6 @@ export interface Model {
 
 // ─── Article ─────────────────────────────────────────────────────────────────
 
-export interface ArticleAuthor {
-  first_name: string | null;
-  last_name: string | null;
-  avatar: string | null;
-  description: string | null;
-  website?: string | null;
-}
-
 export interface Article {
   id: string;
   slug: string;
@@ -106,7 +98,7 @@ export interface Article {
   publish_date: Date;
   category: string | null;
   featured: boolean | null;
-  author?: ArticleAuthor | null;
+  author?: VideoModel | null;
 }
 
 // ─── Comment ─────────────────────────────────────────────────────────────────