refactor state handling to make application available independent of the state

docs/application.md

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+# Application
+
+- It's mainly responsible for
+  - creating and event based [application state](#application-state)
+  - parsing and compiling [application data](#application-data)
+
+## Application state
+
+- [ApplicationContext.ts](./../src/application/Context/ApplicationContext.ts) holds the [CategoryCollectionState](./../src/application/Context/State/CategoryCollectionState.ts)] for each OS
+- Uses [state pattern](https://en.wikipedia.org/wiki/State_pattern)
+- Same instance is shared throughout the application to ensure consistent state
+- 📖 See [Application State | Presentation layer](./presentation.md#application-state) to read more about how the state should be managed by the presentation layer.
+- 📖 See [ApplicationContext.ts](./../src/application/Context/ApplicationContext.ts) to start diving into the state code.
+
+## Application data
+
+- Compiled to `Application` domain object.
+- The scripts are defined and controlled in different data files per OS
+- Enables [data-driven programming](https://en.wikipedia.org/wiki/Data-driven_programming) and easier contributions
+- Application data is defined in collection fil es and
+- 📖 See [Application data | Presentation layer](./presentation.md#application-data) to read how the application data is read by the presentation layer.
+- 📖 See [collection files documentation](./collection-files.md) to read more about how the data files are structured/defined and see [collection yaml files](./../src/application/collections/) to directly check the code.