Update docs

Author: ThomasFarstrike

docs/architecture/filesystem.md

@@ -2,18 +2,20 @@
 
 MicroPythonOS uses a structured filesystem to organize apps, data, and resources.
 
-- **apps/**: Directory for downloaded and installed apps.
+- **apps/**: Directory for downloaded and installed apps. Cleaned up when the app is uninstalled.
     - **com.micropythonos.helloworld/**: Installation directory for HelloWorld App. See [Creating Apps](../apps/creating-apps.md).
 - **builtin/**: Read-only filesystem compiled into the OS, mounted at boot by `main.py`.
     - **apps/**: See [Built-in Apps](../apps/built-in-apps.md).
     - **res/**: Resources (icons, fonts, etc.).
+- **cache/**: Temporary files for each app. Deleted when the app is uninstalled, and may also be deleted without uninstalling the app to free up space.
+- **data/**: Content files independent of specific apps (images, audio, recordings, etc.). Used by apps like Camera, ImageView, Sound Recorder, and Music Player.
 - **lib/**: Libraries and frameworks
     - **mpos/**: MicroPythonOS libraries and frameworks
         - **ui/**: MicroPythonOS User Interface libraries and frameworks
-- **prefs/**: Storage for app data.
+- **prefs/**: App preferences and settings. Cleaned up when the app is uninstalled.
     - **com.micropythonos.helloworld/**: App-specific storage (e.g., `config.json`)
     - **com.micropythonos.settings/**: Storage used by the built-in Settings App
-    - **com.micropythonos.wifi/**: Storage used by the built-in WiFi App
+    - **com_micropythonos_nostr/**: Storage for the Nostr App
 
 This structure ensures a clear separation between system resources, apps, and user data.