Tag blog posts and sign them with a member

Tags are named in every language and made from the page form; the byline is
the member who signs a post on the site. The public API sends both, filters
posts by tag and lists the tags in use.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/Models/Page.php

@@ -18,6 +18,7 @@ use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\BelongsToMany;
 use Illuminate\Database\Eloquent\SoftDeletes;
 use Spatie\Translatable\HasTranslations;
 
@@ -26,7 +27,7 @@ use Spatie\Translatable\HasTranslations;
  * @property array<string, string> $slug
  */
 #[Fillable([
-    'category_id', 'author_id', 'title', 'slug', 'excerpt', 'body',
+    'category_id', 'author_id', 'byline_member_id', 'title', 'slug', 'excerpt', 'body',
     'meta_title', 'meta_description', 'status', 'featured_image',
     'featured_image_alt', 'is_featured', 'published_at', 'unpublish_at',
 ])]
@@ -146,6 +147,25 @@ class Page extends Model
         return $this->belongsTo(User::class, 'author_id');
     }
 
+    /**
+     * Who signs it on the site: a member, with a profile to link to. Not the
+     * account that typed it in, which is `author` and stays in the panel.
+     *
+     * @return BelongsTo<Member, $this>
+     */
+    public function byline(): BelongsTo
+    {
+        return $this->belongsTo(Member::class, 'byline_member_id');
+    }
+
+    /**
+     * @return BelongsToMany<Tag, $this>
+     */
+    public function tags(): BelongsToMany
+    {
+        return $this->belongsToMany(Tag::class);
+    }
+
     /**
      * Publicly visible pages: published and not scheduled for the future.
      *