Configuration and architecture v0.7.0

This release makes Vault Issues configurable for different vault structures and prepares the plugin for public distribution.
This release also focuses on the internal architecture and reliability of Vault Issues as the project moves toward a stable release.

Added:

• Configurable issues folder
• Configurable issue ID prefix
• Default priority setting
• Existing default layout and sorting preferences
• Improved migration of issues created by earlier versions
• Expanded automated test suite
• Tests for issue IDs, statuses, sorting, filtering, settings, and metadata handling
• Automated tests in GitHub Actions

Improved

• Refactored the Issues view into smaller, focused modules
• Improved separation between UI, filtering, persistence, and issue-management logic
• Improved handling of malformed or incomplete Markdown issue files
• Improved maintainability of the TypeScript codebase

This release focuses on removing hardcoded assumptions while preserving the Markdown-first design of the plugin. The focus is on making the existing functionality safer, easier to test, and easier to extend.