Hard-filter /portfolio/:slug when it matches a category

Category chips (e.g. /portfolio/photography) now show only that
category — empty if none. Audience views like /portfolio/game-dev
still use prioritization.

client/src/lib/api.ts

@@ -105,12 +105,16 @@ export interface ListMeta {
   perPage: number;
   total: number;
   totalPages: number;
+  /** all | category (hard filter) | view (audience prioritization) */
+  mode?: "all" | "category" | "view";
+  category?: Category;
   view?: {
     slug: string;
     name: string;
     description?: string | null;
     categories?: Category[];
   };
+  search?: boolean;
 }
 
 async function request<T>(path: string, init?: RequestInit): Promise<T> {