chore(security): enhance environment configuration, CI workflows, and wallet daemon with security improvements

- Restructure .env.example with security-focused documentation, service-specific environment file references, and AWS Secrets Manager integration
- Update CLI tests workflow to single Python 3.13 version, add pytest-mock dependency, and consolidate test execution with coverage
- Add comprehensive security validation to package publishing workflow with manual approval gates, secret scanning, and release

migration_examples/basic_migration.py

@@ -0,0 +1,40 @@
+#!/usr/bin/env python3
+"""
+Basic Migration Example
+
+Shows how to migrate from direct CUDA calls to the new abstraction layer.
+"""
+
+# BEFORE (Direct CUDA)
+# from high_performance_cuda_accelerator import HighPerformanceCUDAZKAccelerator
+# 
+# accelerator = HighPerformanceCUDAZKAccelerator()
+# if accelerator.initialized:
+#     result = accelerator.field_add_cuda(a, b)
+
+# AFTER (Abstraction Layer)
+import numpy as np
+from gpu_acceleration import GPUAccelerationManager, create_gpu_manager
+
+# Method 1: Auto-detect backend
+gpu = create_gpu_manager()
+gpu.initialize()
+
+a = np.array([1, 2, 3, 4], dtype=np.uint64)
+b = np.array([5, 6, 7, 8], dtype=np.uint64)
+
+result = gpu.field_add(a, b)
+print(f"Field addition result: {result}")
+
+# Method 2: Context manager (recommended)
+from gpu_acceleration import GPUAccelerationContext
+
+with GPUAccelerationContext() as gpu:
+    result = gpu.field_mul(a, b)
+    print(f"Field multiplication result: {result}")
+
+# Method 3: Quick functions
+from gpu_acceleration import quick_field_add
+
+result = quick_field_add(a, b)
+print(f"Quick field addition: {result}")