Fix vertical overflow by removing nested Scaffold architecture

- Remove nested Scaffold from ScoringPage (now uses LayoutBuilder)
- Use proper constraint-based height calculation instead of MediaQuery
- Maintain score preservation across navigation without nested scaffolds
- Fix viewport architecture to work within MainNavigationPage body
- Minor keypad layout adjustment (77%/23% flex ratio)

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

tools/test_flutter.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python3
+"""
+Test Flutter executable finding.
+"""
+
+from flutter_rename import FlutterRenamer
+
+def test_flutter_finder():
+    """Test Flutter executable detection."""
+    renamer = FlutterRenamer()
+    
+    print("Testing Flutter executable detection...")
+    flutter_cmd = renamer.find_flutter_executable()
+    
+    if flutter_cmd:
+        print(f"✓ Found Flutter: {flutter_cmd}")
+        
+        # Test if it actually works
+        import subprocess
+        try:
+            result = subprocess.run([flutter_cmd, "--version"], capture_output=True, text=True, timeout=10)
+            if result.returncode == 0:
+                print("✓ Flutter command works!")
+                print(f"Version output: {result.stdout.split()[1] if len(result.stdout.split()) > 1 else 'Unknown'}")
+            else:
+                print(f"✗ Flutter command failed: {result.stderr}")
+        except Exception as e:
+            print(f"✗ Error testing Flutter: {e}")
+    else:
+        print("✗ Flutter not found")
+
+if __name__ == "__main__":
+    test_flutter_finder()