Moved all web development service and pricing plan data from `web-design/index.vue` to a new `config/web-dev-services.ts` file.
- Centralizes service definitions for easier maintenance and scalability.
- Simplifies the `web-design` page by making it data-driven.
- Replaces static links with dynamic `onClick` handlers that generate a pre-filled WhatsApp message for inquiries.
This commit introduces the new 'Web Design' service page.
- Creates the route to showcase pricing plans for Landing Pages and Official Websites.
- Uses a tabbed layout to organize the different service tiers.
- Adds a '网展开发' link to the main navigation bar in the default layout for easy access.