[Linux] Implement AccessibilityManager class (#9)

* Initial plan

* Implement AccessibilityManager for Linux platform

Co-authored-by: lijy91 <[email protected]>

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: lijy91 <[email protected]>

Author: Copilot

src/platform/linux/accessibility_manager_linux.cpp

@@ -0,0 +1,60 @@
+#include "../../accessibility_manager.h"
+
+#include <cstdlib>
+#include <iostream>
+
+// Import GTK headers for accessibility support
+#include <gtk/gtk.h>
+#include <glib.h>
+
+namespace nativeapi {
+
+void AccessibilityManager::Enable() {
+  // On Linux, accessibility is primarily handled by AT-SPI (Assistive Technology Service Provider Interface)
+  // Applications typically don't need to explicitly "enable" accessibility - it's handled by the system
+  // However, we can ensure GTK accessibility features are available
+  
+  // Initialize GTK if not already initialized (for accessibility bridge)
+  if (!gdk_display_get_default()) {
+    // Try to initialize GTK silently if not already done
+    gtk_init_check(nullptr, nullptr);
+  }
+  
+  // The accessibility bridge in GTK is automatically enabled when accessibility is needed
+  // No explicit action needed - this is a no-op on Linux as accessibility is system-managed
+}
+
+bool AccessibilityManager::IsEnabled() {
+  // Check if accessibility features are enabled on the Linux system
+  
+  // Method 1: Check if AT-SPI accessibility bus is running
+  // This is the most reliable way to detect if accessibility is active
+  const char* at_spi_bus = g_getenv("AT_SPI_BUS");
+  if (at_spi_bus && strlen(at_spi_bus) > 0) {
+    return true;
+  }
+  
+  // Method 2: Check for common accessibility environment variables
+  const char* accessibility_enabled = g_getenv("GNOME_ACCESSIBILITY");
+  if (accessibility_enabled && g_ascii_strcasecmp(accessibility_enabled, "1") == 0) {
+    return true;
+  }
+  
+  // Method 3: Check if screen reader (Orca) is running
+  // This is a fallback method for older systems
+  if (system("pgrep -x orca > /dev/null 2>&1") == 0) {
+    return true;
+  }
+  
+  // Method 4: Check GTK accessibility settings if available
+  // Some desktop environments set this when accessibility is enabled
+  const char* gtk_modules = g_getenv("GTK_MODULES");
+  if (gtk_modules && strstr(gtk_modules, "gail") != nullptr) {
+    return true;
+  }
+  
+  // If none of the above methods detect accessibility, assume it's disabled
+  return false;
+}
+
+}  // namespace nativeapi