Fix dependency detection in build script

✅ FIXED DEPENDENCY DETECTION:
- Corrected import testing logic for PyQt6 and PyInstaller
- Now properly detects installed packages instead of false negatives
- Uses correct import names: PyQt6.QtWidgets and PyInstaller
- Eliminates false 'missing dependency' errors when packages are installed

TECHNICAL FIX:
- Fixed import_tests dictionary for accurate package detection
- Proper case-sensitive import checking
- Resolves issue where installed packages were incorrectly flagged as missing

build_usb_creator.py

@@ -22,13 +22,20 @@ def check_dependencies():
     
     missing_packages = []
     
-    for package in packages:
+    # Test actual imports that the application uses
+    import_tests = {
+        "PyQt6": "PyQt6.QtWidgets",
+        "pyinstaller": "PyInstaller"
+    }
+    
+    for package_name in packages:
         try:
-            __import__(package.lower().replace('-', '_'))
-            print(f"✓ {package} found")
+            import_name = import_tests.get(package_name, package_name)
+            __import__(import_name)
+            print(f"✓ {package_name} found")
         except ImportError:
-            print(f"✗ {package} missing")
-            missing_packages.append(package)
+            print(f"✗ {package_name} missing")
+            missing_packages.append(package_name)
     
     if missing_packages:
         print("\nMissing dependencies found!")