feat: add user profile views and library management

- Add UserProfileView and UserProfileViewModel for iOS
- Implement user library API endpoint (/api/users/[username]/library)
- Add DELETE /api/progress/[slug] endpoint for removing books from library
- Integrate subscription feed in home API
- Update Xcode project with new profile components

ui/src/lib/server/pocketbase.ts

@@ -127,6 +127,14 @@ async function pbPatch(path: string, body: unknown): Promise<Response> {
 	});
 }
 
+async function pbDelete(path: string): Promise<Response> {
+	const token = await getToken();
+	return fetch(`${PB_URL}${path}`, {
+		method: 'DELETE',
+		headers: { Authorization: `Bearer ${token}` }
+	});
+}
+
 interface PBList<T> {
 	items: T[];
 	totalItems: number;
@@ -286,10 +294,41 @@ export async function setProgress(
 		if (!res.ok) {
 			const body = await res.text().catch(() => '');
 			log.error('pocketbase', 'setProgress POST failed', { slug, chapter, status: res.status, body });
-		}
 	}
 }
 
+/**
+ * Delete progress entry for a specific book (removes from library/continue reading).
+ */
+export async function deleteProgress(
+	sessionId: string,
+	slug: string,
+	userId?: string
+): Promise<void> {
+	const existing = await listOne<Progress & { id: string }>(
+		'progress',
+		progressFilter(sessionId, slug, userId)
+	);
+
+	if (!existing) {
+		log.debug('pocketbase', 'deleteProgress: no record found', { sessionId, slug, userId });
+		return;
+	}
+
+	const res = await pbDelete(`/api/collections/progress/records/${existing.id}`);
+	if (!res.ok) {
+		const body = await res.text().catch(() => '');
+		log.error('pocketbase', 'deleteProgress failed', {
+			slug,
+			id: existing.id,
+			status: res.status,
+			body
+		});
+		throw new Error(`Failed to delete progress: ${res.status}`);
+	}
+	log.info('pocketbase', 'deleteProgress success', { slug, id: existing.id });
+}
+
 /**
  * Merge anonymous session progress into a user account on login/register.
  *