Updated development index, Sonador architecture reference, frontend development index, Cornerstone 3D page, and Cornerstone 3D Interaction Patterns page to provide better linking and signposting between content.

dev.index.md

@@ -4,6 +4,17 @@ Sonador is an open source platform composed of community developed components, l
 Development of the project's first-party libraries happens on [a GitLab instance](https://code.oak-tree.tech) provided by [Oak-Tree Technologies](https://www.oak-tree.tech), under the [Medical Imaging](https://code.oak-tree.tech/oak-tree/medical-imaging) group. **Community contributions are welcomed and greatly appreciated.** _Refer to [How to Contribute](dev.contributing) for ideas on how to contribute._
 
 
+#### 📐 Architecture
+* [Sonador Platform Architecture (Backend + Frontend)](dev.architecture-sonador)
+* [Sonador Viewer Architecture (OHIF + Cornerstone3D)](dev.architecture-sonador.ohif)
+
+
+#### 🧭 Developer Reference
+* [Frontend Developer Index (Sonador Viewer)](dev.ohif-frontend)
+  - [Cornerstone3D Integration Reference](dev.ohif-frontend.cornerstone3d-architecture)
+  - [Cornerstone3D Tools and Interaction Patterns](dev.ohif-frontend.cornerstone3d-tools)
+  - [React-VTKJS-Viewport](dev.ohif-frontend.react-vtkjs-viewports): overview of 2D/3D rendering classes, important properties, and component lifecycle
+
 
 ## [Development Environment](https://code.oak-tree.tech/oak-tree/medical-imaging/imaging-development-env)
 <img align="right" src="uploads/img/sonador.development-env.svg">