feat: Implement existing repository analysis feature

- Added ExistingRepoEntryClient component for user input of GitHub repository URLs.
- Updated ExistingRepoEntryPage to utilize the new client component and set appropriate metadata.
- Enhanced global styles with new loading animations for repository scanning.
- Introduced new utility functions for normalizing GitHub repository URLs.
- Created RepoScanLoader component for displaying loading states during repository scans.
- Updated stack wizard components to support initial stack steps and labels.
- Improved input handling and validation for GitHub URLs in the Hero component.
- Added scanning and pre-filling logic for wizard responses based on repository analysis.
- Defined new types for repository scan summaries and responses.
- Refactored existing components and utilities to accommodate the new features and improve code organization.

Author: spivx

README.md

@@ -1,6 +1,5 @@
 ![devcontext logo](public/logo.png)
 
-# devcontext
 
 Build high-signal agent and instruction files from community-proven best practices.