feat: add companies as top-level container for projects with departments

- Company → Project → (Locations + Departments) hierarchy
- Company CRUD (add, edit, delete) with AJAX
- Projects are created under a company via inline strip
- Two-column project body: Locations | Departments
- Stats show companies, projects, locations, departments, active projects
- Dynamic stat counters update on add/delete without page reload

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

app/Models/Settings/Company.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace App\Models\Settings;
+
+use Illuminate\Database\Eloquent\Model;
+
+class Company extends Model
+{
+    protected $table = 'settings_companies';
+
+    protected $fillable = ['name', 'is_active'];
+
+    protected $casts = ['is_active' => 'boolean'];
+
+    public function projects(): \Illuminate\Database\Eloquent\Relations\HasMany
+    {
+        return $this->hasMany(ProjectSetting::class, 'company_id');
+    }
+}