feat: rebrand AgendaPro -> AgendaMax + calendar fixes + current-week demo seed

- Rebrand all user-facing text to AgendaMax
- Fix sidebar scrolling: card container no longer overflows html (flex h-full min-h-0)
- Fix calendar toolbar hover: active buttons keep readable contrast
- Sticky calendar toolbar (month/week/day always visible on scroll)
- Seed guarantees 2-4 appointments per day for current week (Mon-Sat)

src/lib/publicApi.ts

@@ -1,3 +1,6 @@
+import type { BookResponse } from "../../shared/types";
+export type { BookResponse };
+
 const BASE = "/api/public";
 
 export interface PublicBusiness {
@@ -64,20 +67,6 @@ export interface BookPayload {
   client: BookClient;
 }
 
-export interface BookResponse {
-  appointment: {
-    id: number;
-    start_at: string;
-    price: number;
-    service_name: string;
-    employee_id: number;
-    employee_name: string;
-    reasons: string[];
-  };
-  business: { name: string; currency_symbol: string };
-  client_created: boolean;
-}
-
 async function request<T>(path: string, init?: RequestInit): Promise<T> {
   const res = await fetch(`${BASE}${path}`, {
     ...init,