Fix --exec interactive prompt bug and create comprehensive test suite

Major fixes:
- Fixed --exec entering Python REPL instead of game loop
- Resolved screenshot transparency issue (requires timer callbacks)
- Added debug output to trace Python initialization

Test suite created:
- 13 comprehensive tests covering all Python-exposed methods
- Tests use timer callback pattern for proper game loop interaction
- Discovered multiple critical bugs and missing features

Critical bugs found:
- Grid class segfaults on instantiation (blocks all Grid functionality)
- Issue #78 confirmed: Middle mouse click sends 'C' keyboard event
- Entity property setters have argument parsing errors
- Sprite texture setter returns improper error
- keypressScene() segfaults on non-callable arguments

Documentation updates:
- Updated CLAUDE.md with testing guidelines and TDD practices
- Created test reports documenting all findings
- Updated ROADMAP.md with test results and new priorities

The Grid segfault is now the highest priority as it blocks all Grid-based functionality.

tests/automation_screenshot_test.py

@@ -0,0 +1,96 @@
+#!/usr/bin/env python3
+"""Test for mcrfpy.automation.screenshot()"""
+import mcrfpy
+from mcrfpy import automation
+from datetime import datetime
+import os
+import sys
+import time
+
+runs = 0
+def test_screenshot(*args):
+    """Test screenshot functionality"""
+    #global runs
+    #runs += 1
+    #if runs < 2:
+    #    print("tick")
+    #    return
+    #print("tock")
+    #mcrfpy.delTimer("timer1")
+    # Create a scene with some visual elements
+    mcrfpy.createScene("screenshot_test")
+    mcrfpy.setScene("screenshot_test")
+    ui = mcrfpy.sceneUI("screenshot_test")
+    
+    # Add some colorful elements
+    frame1 = mcrfpy.Frame(10, 10, 200, 150,
+                         fill_color=mcrfpy.Color(255, 0, 0),
+                         outline_color=mcrfpy.Color(255, 255, 255),
+                         outline=3.0)
+    ui.append(frame1)
+    
+    frame2 = mcrfpy.Frame(220, 10, 200, 150,
+                         fill_color=mcrfpy.Color(0, 255, 0),
+                         outline_color=mcrfpy.Color(0, 0, 0),
+                         outline=2.0)
+    ui.append(frame2)
+    
+    caption = mcrfpy.Caption(mcrfpy.Vector(10, 170),
+                            text="Screenshot Test Scene",
+                            fill_color=mcrfpy.Color(255, 255, 0))
+    caption.size = 24
+    ui.append(caption)
+    
+    # Test multiple screenshots
+    timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
+    filenames = []
+    
+    # Test 1: Basic screenshot
+    try:
+        filename1 = f"test_screenshot_basic_{timestamp}.png"
+        result = automation.screenshot(filename1)
+        filenames.append(filename1)
+        print(f"✓ Basic screenshot saved: {filename1} (result: {result})")
+    except Exception as e:
+        print(f"✗ Basic screenshot failed: {e}")
+        print("FAIL")
+        sys.exit(1)
+    
+    # Test 2: Screenshot with special characters in filename
+    try:
+        filename2 = f"test_screenshot_special_chars_{timestamp}_test.png"
+        result = automation.screenshot(filename2)
+        filenames.append(filename2)
+        print(f"✓ Screenshot with special filename saved: {filename2} (result: {result})")
+    except Exception as e:
+        print(f"✗ Special filename screenshot failed: {e}")
+    
+    # Test 3: Invalid filename (if applicable)
+    try:
+        result = automation.screenshot("")
+        print(f"✗ Empty filename should fail but returned: {result}")
+    except Exception as e:
+        print(f"✓ Empty filename correctly rejected: {e}")
+    
+    # Check files exist immediately
+    files_found = 0
+    for filename in filenames:
+        if os.path.exists(filename):
+            size = os.path.getsize(filename)
+            print(f"✓ File exists: {filename} ({size} bytes)")
+            files_found += 1
+        else:
+            print(f"✗ File not found: {filename}")
+    
+    if files_found == len(filenames):
+        print("PASS")
+        sys.exit(0)
+    else:
+        print("FAIL")
+        sys.exit(1)
+
+print("Set callback")
+mcrfpy.setTimer("timer1", test_screenshot, 1000)
+# Run the test immediately
+#test_screenshot()
+