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/api/oauth.ts

@@ -0,0 +1,93 @@
+/**
+ * OAuth API
+ * Handles OAuth authentication flows with various providers
+ */
+
+import apiClient from './client';
+
+export interface OAuthProvider {
+  name: string;
+  display_name: string;
+  icon: string;
+}
+
+export interface OAuthAuthorizationResponse {
+  authorization_url: string;
+}
+
+export interface OAuthTokenResponse {
+  access: string;
+  refresh: string;
+  user: {
+    id: number;
+    username: string;
+    email: string;
+    name: string;
+    role: string;
+    avatar_url?: string;
+    is_staff: boolean;
+    is_superuser: boolean;
+    business?: number;
+    business_name?: string;
+    business_subdomain?: string;
+  };
+}
+
+export interface OAuthConnection {
+  id: string;
+  provider: string;
+  provider_user_id: string;
+  email?: string;
+  connected_at: string;
+}
+
+/**
+ * Get list of enabled OAuth providers
+ */
+export const getOAuthProviders = async (): Promise<OAuthProvider[]> => {
+  const response = await apiClient.get<{ providers: OAuthProvider[] }>('/api/auth/oauth/providers/');
+  return response.data.providers;
+};
+
+/**
+ * Initiate OAuth flow - get authorization URL
+ */
+export const initiateOAuth = async (provider: string): Promise<OAuthAuthorizationResponse> => {
+  const response = await apiClient.get<OAuthAuthorizationResponse>(
+    `/api/auth/oauth/${provider}/authorize/`
+  );
+  return response.data;
+};
+
+/**
+ * Handle OAuth callback - exchange code for tokens
+ */
+export const handleOAuthCallback = async (
+  provider: string,
+  code: string,
+  state: string
+): Promise<OAuthTokenResponse> => {
+  const response = await apiClient.post<OAuthTokenResponse>(
+    `/api/auth/oauth/${provider}/callback/`,
+    {
+      code,
+      state,
+    }
+  );
+  return response.data;
+};
+
+/**
+ * Get user's connected OAuth accounts
+ */
+export const getOAuthConnections = async (): Promise<OAuthConnection[]> => {
+  const response = await apiClient.get<{ connections: OAuthConnection[] }>('/api/auth/oauth/connections/');
+  return response.data.connections;
+};
+
+/**
+ * Disconnect an OAuth account
+ */
+export const disconnectOAuth = async (provider: string): Promise<void> => {
+  await apiClient.delete(`/api/auth/oauth/connections/${provider}/`);
+};