Quick navigation in DocC Render

DocC Render is an open-sourced project that let us visualize `.doccarchive` on the web, it renders the compiled Swift codebase documentation in a clean and standardized UI making it easier for developers to learn, review and share packages and frameworks documentation. The codebase documentation can get very large easily and right now the DocC rendered website only provides certain filter and search capabilities through the sidebar, but besides that, there's no convenient way to explore the docs. In this project we are going to design and implement the “Quick Navigation” feature into swift-docc-render, allowing users to navigate and discover documentation symbols and files easily. Similar to "Open Quickly" in Xcode and other web-based documentation sites we will let the user type and find what they are looking for through some cool capabilities including fuzzy search, quick access to recent symbols, and keyboard navigation.