Initial commit: SmoothSchedule multi-tenant scheduling platform

This commit includes:
- Django backend with multi-tenancy (django-tenants)
- React + TypeScript frontend with Vite
- Platform administration API with role-based access control
- Authentication system with token-based auth
- Quick login dev tools for testing different user roles
- CORS and CSRF configuration for local development
- Docker development environment setup

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

frontend/src/components/PlatformSidebar.tsx

@@ -0,0 +1,85 @@
+import React from 'react';
+import { useTranslation } from 'react-i18next';
+import { Link, useLocation } from 'react-router-dom';
+import { LayoutDashboard, Building2, MessageSquare, Settings, Users, Shield } from 'lucide-react';
+import { User } from '../types';
+import SmoothScheduleLogo from './SmoothScheduleLogo';
+
+interface PlatformSidebarProps {
+  user: User;
+  isCollapsed: boolean;
+  toggleCollapse: () => void;
+}
+
+const PlatformSidebar: React.FC<PlatformSidebarProps> = ({ user, isCollapsed, toggleCollapse }) => {
+  const { t } = useTranslation();
+  const location = useLocation();
+
+  const getNavClass = (path: string) => {
+    const isActive = location.pathname === path || (path !== '/' && location.pathname.startsWith(path));
+    const baseClasses = `flex items-center gap-3 py-2 text-sm font-medium rounded-md transition-colors`;
+    const collapsedClasses = isCollapsed ? 'px-3 justify-center' : 'px-3';
+    const activeClasses = 'bg-gray-700 text-white';
+    const inactiveClasses = 'text-gray-400 hover:text-white hover:bg-gray-800';
+    return `${baseClasses} ${collapsedClasses} ${isActive ? activeClasses : inactiveClasses}`;
+  };
+  
+  const isSuperuser = user.role === 'superuser';
+  const isManager = user.role === 'platform_manager';
+
+  return (
+    <div className={`flex flex-col h-full bg-gray-900 text-white shrink-0 border-r border-gray-800 transition-all duration-300 ${isCollapsed ? 'w-20' : 'w-64'}`}>
+      <button
+        onClick={toggleCollapse}
+        className={`flex items-center gap-3 w-full text-left px-6 py-6 border-b border-gray-800 ${isCollapsed ? 'justify-center' : ''} hover:bg-gray-800 transition-colors focus:outline-none`}
+        aria-label={isCollapsed ? "Expand sidebar" : "Collapse sidebar"}
+      >
+        <SmoothScheduleLogo className="w-10 h-10 shrink-0" />
+        {!isCollapsed && (
+          <div className="overflow-hidden">
+            <h1 className="font-bold text-sm tracking-wide uppercase text-gray-100 truncate">Smooth Schedule</h1>
+            <p className="text-xs text-gray-500 capitalize truncate">{user.role.replace('_', ' ')}</p>
+          </div>
+        )}
+      </button>
+
+      <nav className="flex-1 px-4 py-6 space-y-1 overflow-y-auto">
+        <p className={`text-xs font-semibold text-gray-500 uppercase tracking-wider mb-2 ${isCollapsed ? 'text-center' : 'px-3'}`}>{isCollapsed ? 'Ops' : 'Operations'}</p>
+        {(isSuperuser || isManager) && (
+            <Link to="/platform/dashboard" className={getNavClass('/platform/dashboard')} title={t('nav.platformDashboard')}>
+                <LayoutDashboard size={18} className="shrink-0" />
+                {!isCollapsed && <span>{t('nav.dashboard')}</span>}
+            </Link>
+        )}
+        <Link to="/platform/businesses" className={getNavClass("/platform/businesses")} title={t('nav.businesses')}>
+          <Building2 size={18} className="shrink-0" />
+          {!isCollapsed && <span>{t('nav.businesses')}</span>}
+        </Link>
+        <Link to="/platform/users" className={getNavClass('/platform/users')} title={t('nav.users')}>
+          <Users size={18} className="shrink-0" />
+          {!isCollapsed && <span>{t('nav.users')}</span>}
+        </Link>
+        <Link to="/platform/support" className={getNavClass('/platform/support')} title={t('nav.support')}>
+          <MessageSquare size={18} className="shrink-0" />
+          {!isCollapsed && <span>{t('nav.support')}</span>}
+        </Link>
+
+        {isSuperuser && (
+          <>
+            <p className={`text-xs font-semibold text-gray-500 uppercase tracking-wider mb-2 mt-8 ${isCollapsed ? 'text-center' : 'px-3'}`}>{isCollapsed ? 'Sys' : 'System'}</p>
+            <Link to="/platform/staff" className={getNavClass('/platform/staff')} title={t('nav.staff')}>
+              <Shield size={18} className="shrink-0" />
+              {!isCollapsed && <span>{t('nav.staff')}</span>}
+            </Link>
+            <Link to="/platform/settings" className={getNavClass('/platform/settings')} title={t('nav.platformSettings')}>
+              <Settings size={18} className="shrink-0" />
+              {!isCollapsed && <span>{t('nav.platformSettings')}</span>}
+            </Link>
+          </>
+        )}
+      </nav>
+    </div>
+  );
+};
+
+export default PlatformSidebar;