Build a Private Bookmark Manager with Base44

Create a small, production-ready web app named "Bookmark Pocket". PURPOSE A private personal bookmark manager where the signed-in owner can save, organize, search, edit, favorite, and delete useful links. KEEP THE BUILD SMALL Use Base44 native features only. Do not add external APIs, AI features, payments, email, social login, analytics, images, file uploads, agents, automations, or third-party integrations. Do not ask follow-up questions. Use the exact decisions below and build the complete app in one pass. AUTHENTICATION AND ACCESS - Use Base44's built-in email/password authentication. - Require sign-in to access the app. - Do not allow anonymous data access. - Each user may read, create, update, and delete only their own bookmarks. - Enforce ownership in Base44 entity permissions, not only in the interface. - Users must never see another user's records. DATA Create one entity named Bookmark with: - title: required string - url: required URL string - category: required string - notes: optional multiline string - isFavorite: boolean, default false - createdBy: owner/user reference populated automatically - createdAt and updatedAt timestamps INTERFACE - Responsive single-page dark interface with a clean, minimal design. - Header with app name, total bookmark count, and sign-out control. - Compact form to add a bookmark with Title, URL, Category, Notes, and Favorite. - Validate required fields and URL format with friendly inline messages. - Display bookmarks as readable cards. - Each card shows title, domain/URL, category, optional notes, favorite status, and created date. - Clicking the title or an Open button launches the URL in a new tab with safe link attributes. - Search title, URL, category, and notes. - Category filter with an All option. - Favorites-only toggle. - Sort newest first by default. - Edit in a small dialog or inline form. - Delete only after confirmation. - Clear loading, success, error, no-results, and empty states. - Add three sample bookmarks only if they can be created as records owned by the currently signed-in user; otherwise start empty with a helpful empty state. DESIGN - Near-black background, charcoal panels, off-white text, muted gray secondary text, and one restrained amber accent. - Use a normal readable sans-serif body font. - Subtle borders, medium corner radius, modest shadows, and accessible focus states. - Avoid excessive animation, gradients, glassmorphism, oversized headings, decorative illustrations, and complex navigation. - Mobile layout must remain easy to use. QUALITY AND SECURITY - Use semantic labels and keyboard-accessible controls. - Sanitize and validate URLs. - Never expose service credentials or privileged APIs in client code. - Verify create, edit, favorite, filtering, external-link opening, and delete flows. - Keep code and components simple and reusable. - Prepare the app for Base44 publishing. Build this now with sensible defaults and do not ask any questions.