feat: Added documentation for OHIF-v3 (#2450)

* Added docs with new screenshots

* Added doc to architecture

* Added documentations to various extension modules

* Added more documentation to modes

* Added docs to managers

* Added docs for services

* Fixed deployment docs

* Added white labelling documentation

* Added i18n docs and measurement export

docs/latest/userManuals/viewer/index.md

@@ -0,0 +1,29 @@
+# Viewer
+- [Viewer](./index.md)
+  - [Overview](./index.md#overview)
+  - [Study Panel](./studyPanel/study-panel.md)
+  - [Measurement Panel](./measurementPanel/measurement-panel.md)
+  - [Toolbar](./toolbar/toolbar.md)
+  - [HotKeys](./hotkeys/hotkeys.md)
+
+
+# Overview
+When you open a mode, viewport, toolbar and panels of the mode get shown.
+It is important to note that each mode has a different UI, which serves its purpose.
+Here we explain various components of `Basic Viewer` mode which includes measurement
+tracking functionalities.
+
+Basic viewer mode (longitudinal):
+
+![user-viewer](../../assets/img/user-viewer.png)
+
+Let's break different aspects of the viewer to the main components:
+
+- Left Panel (study panel): displays series thumbnails with series details
+- Viewport: renders the image and displays annotations
+- Right Panel (measurements): displays annotations details
+- Toolbar: displays tools and logo
+
+![user-viewer-components](../../assets/img/user-viewer-components.png)
+
+Now, we explain each component and its sub-elements in detail.