OPTIONAL MODEL RELATION — add inside app/Models/Post.php

public function brandProfile()
{
    return $this->belongsTo(\App\Models\BrandProfile::class);
}

Brand profile selection is not wired into the original composer yet. Add a brand_profile_id dropdown to your post form and validate that the selected brand belongs to the current organization before saving. Then pass tone_of_voice, audience and brand_notes to the AI prompt builder.
