Add optional Tone field to Sites for AI content generation

- Add tone column to sites table (nullable string)
- Add TONES constant to Site model with predefined options:
  professional, casual, technical, friendly, formal, humorous,
  conversational, authoritative, inspirational, educational, minimal, detailed
- Update Sites Livewire component to edit tone
- Update Sites view with tone select dropdown in form
- Add tone column to sites table display
- Add tone to SiteResource API response

AI agents can now read the site's tone and use it when generating content.

Generated by Mistral Vibe.
Co-Authored-By: Mistral Vibe <vibe@mistral.ai>

app/Models/Site.php

@@ -11,6 +11,12 @@ class Site extends Model
 
     public const CMS_TYPES = ['wordpress', 'custom', 'other'];
 
+    public const TONES = [
+        'professional', 'casual', 'technical', 'friendly',
+        'formal', 'humorous', 'conversational', 'authoritative',
+        'inspirational', 'educational', 'minimal', 'detailed',
+    ];
+
     protected $fillable = [
         'name',
         'url',
@@ -19,5 +25,6 @@ class Site extends Model
         'wp_username',
         'wp_app_password',
         'api_instructions',
+        'tone',
     ];
 }