Add execution_image parameter to Agent for custom Docker images

- Add execution_image field to Agent class for specifying custom Docker images
- Modify get_code_execution_tools() to pass custom image to CodeInterpreterTool
- Add comprehensive tests for the new functionality
- Update documentation with usage examples
- Fixes #2933: Allow customizing CrewAI code executor Docker image

Co-Authored-By: João <joao@crewai.com>

tests/test_agent_custom_execution_image.py

@@ -0,0 +1,82 @@
+import pytest
+from unittest.mock import patch, MagicMock
+from crewai import Agent
+
+
+def test_agent_with_custom_execution_image():
+    """Test that Agent can be created with custom execution image."""
+    agent = Agent(
+        role="Test Agent",
+        goal="Test goal",
+        backstory="Test backstory",
+        allow_code_execution=True,
+        execution_image="my-custom-image:latest"
+    )
+    
+    assert agent.execution_image == "my-custom-image:latest"
+
+
+def test_agent_without_custom_execution_image():
+    """Test that Agent works without custom execution image (default behavior)."""
+    agent = Agent(
+        role="Test Agent", 
+        goal="Test goal",
+        backstory="Test backstory",
+        allow_code_execution=True
+    )
+    
+    assert agent.execution_image is None
+
+
+@patch('crewai.agent.CodeInterpreterTool')
+def test_get_code_execution_tools_with_custom_image(mock_code_interpreter):
+    """Test that get_code_execution_tools passes custom image to CodeInterpreterTool."""
+    agent = Agent(
+        role="Test Agent",
+        goal="Test goal", 
+        backstory="Test backstory",
+        allow_code_execution=True,
+        execution_image="my-custom-image:latest"
+    )
+    
+    tools = agent.get_code_execution_tools()
+    
+    mock_code_interpreter.assert_called_once_with(
+        unsafe_mode=False,
+        default_image_tag="my-custom-image:latest"
+    )
+
+
+@patch('crewai.agent.CodeInterpreterTool')
+def test_get_code_execution_tools_without_custom_image(mock_code_interpreter):
+    """Test that get_code_execution_tools works without custom image."""
+    agent = Agent(
+        role="Test Agent",
+        goal="Test goal",
+        backstory="Test backstory", 
+        allow_code_execution=True
+    )
+    
+    tools = agent.get_code_execution_tools()
+    
+    mock_code_interpreter.assert_called_once_with(unsafe_mode=False)
+
+
+@patch('crewai.agent.CodeInterpreterTool')
+def test_get_code_execution_tools_with_unsafe_mode_and_custom_image(mock_code_interpreter):
+    """Test that both unsafe_mode and custom image work together."""
+    agent = Agent(
+        role="Test Agent",
+        goal="Test goal",
+        backstory="Test backstory",
+        allow_code_execution=True,
+        code_execution_mode="unsafe",
+        execution_image="my-custom-image:latest"
+    )
+    
+    tools = agent.get_code_execution_tools()
+    
+    mock_code_interpreter.assert_called_once_with(
+        unsafe_mode=True,
+        default_image_tag="my-custom-image:latest"
+    )