refactor(platform): replace platform checks with capability-based system

- Add PlatformCapabilities interface to define available features
- Remove isWeb(), isCapacitor(), isElectron(), isPyWebView() methods
- Update platform services to implement getCapabilities()
- Refactor DataExportSection to use capability checks instead of platform checks
- Improve platform abstraction and separation of concerns
- Make platform-specific logic more maintainable and extensible

This change decouples components from specific platform implementations,
making the codebase more maintainable and easier to extend with new platforms.

src/services/PlatformService.ts

@@ -9,13 +9,38 @@ export interface ImageResult {
   fileName: string;
 }
 
+/**
+ * Platform capabilities interface defining what features are available
+ * on the current platform implementation
+ */
+export interface PlatformCapabilities {
+  /** Whether the platform supports native file system access */
+  hasFileSystem: boolean;
+  /** Whether the platform supports native camera access */
+  hasCamera: boolean;
+  /** Whether the platform is a mobile device */
+  isMobile: boolean;
+  /** Whether the platform is iOS specifically */
+  isIOS: boolean;
+  /** Whether the platform supports native file download */
+  hasFileDownload: boolean;
+  /** Whether the platform requires special file handling instructions */
+  needsFileHandlingInstructions: boolean;
+}
+
 /**
  * Platform-agnostic interface for handling platform-specific operations.
  * Provides a common API for file system operations, camera interactions,
- * platform detection, and deep linking across different platforms
- * (web, mobile, desktop).
+ * and platform detection across different platforms (web, mobile, desktop).
  */
 export interface PlatformService {
+  // Platform capabilities
+  /**
+   * Gets the current platform's capabilities
+   * @returns Object describing what features are available on this platform
+   */
+  getCapabilities(): PlatformCapabilities;
+
   // File system operations
   /**
    * Reads the contents of a file at the specified path.
@@ -59,32 +84,6 @@ export interface PlatformService {
    */
   pickImage(): Promise<ImageResult>;
 
-  // Platform specific features
-  /**
-   * Checks if the current platform is Capacitor (mobile).
-   * @returns true if running on Capacitor
-   */
-  isCapacitor(): boolean;
-
-  /**
-   * Checks if the current platform is Electron (desktop).
-   * @returns true if running on Electron
-   */
-  isElectron(): boolean;
-
-  /**
-   * Checks if the current platform is PyWebView.
-   * @returns true if running on PyWebView
-   */
-  isPyWebView(): boolean;
-
-  /**
-   * Checks if the current platform is web browser.
-   * @returns true if running in a web browser
-   */
-  isWeb(): boolean;
-
-  // Deep linking
   /**
    * Handles deep link URLs for the application.
    * @param url - The deep link URL to handle