refactor: Major reorganization of optimization_engine module structure

BREAKING CHANGE: Module paths have been reorganized for better maintainability.
Backwards compatibility aliases with deprecation warnings are provided.

New Structure:
- core/           - Optimization runners (runner, intelligent_optimizer, etc.)
- processors/     - Data processing
  - surrogates/   - Neural network surrogates
- nx/             - NX/Nastran integration (solver, updater, session_manager)
- study/          - Study management (creator, wizard, state, reset)
- reporting/      - Reports and analysis (visualizer, report_generator)
- config/         - Configuration management (manager, builder)
- utils/          - Utilities (logger, auto_doc, etc.)
- future/         - Research/experimental code

Migration:
- ~200 import changes across 125 files
- All __init__.py files use lazy loading to avoid circular imports
- Backwards compatibility layer supports old import paths with warnings
- All existing functionality preserved

To migrate existing code:
  OLD: from optimization_engine.nx_solver import NXSolver
  NEW: from optimization_engine.nx.solver import NXSolver

  OLD: from optimization_engine.runner import OptimizationRunner
  NEW: from optimization_engine.core.runner import OptimizationRunner

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

archive/test_scripts/test_adaptive_characterization.py

@@ -12,8 +12,8 @@ Expected behavior:
 import numpy as np
 import optuna
 from pathlib import Path
-from optimization_engine.adaptive_characterization import CharacterizationStoppingCriterion
-from optimization_engine.landscape_analyzer import LandscapeAnalyzer
+from optimization_engine.processors.adaptive_characterization import CharacterizationStoppingCriterion
+from optimization_engine.reporting.landscape_analyzer import LandscapeAnalyzer
 
 
 def simple_smooth_function(trial):

archive/test_scripts/test_neural_surrogate.py

@@ -1,7 +1,7 @@
 """Test neural surrogate integration."""
 
 import time
-from optimization_engine.neural_surrogate import create_surrogate_for_study
+from optimization_engine.processors.surrogates.neural_surrogate import create_surrogate_for_study
 
 print("Testing Neural Surrogate Integration")
 print("=" * 60)

archive/test_scripts/test_nn_surrogate.py

@@ -7,7 +7,7 @@ project_root = Path(__file__).parent
 sys.path.insert(0, str(project_root))
 sys.path.insert(0, str(project_root / 'atomizer-field'))
 
-from optimization_engine.neural_surrogate import create_parametric_surrogate_for_study
+from optimization_engine.processors.surrogates.neural_surrogate import create_parametric_surrogate_for_study
 
 # Create surrogate
 print("Creating parametric surrogate...")

archive/test_scripts/test_parametric_surrogate.py

@@ -1,7 +1,7 @@
 """Test parametric surrogate integration."""
 
 import time
-from optimization_engine.neural_surrogate import create_parametric_surrogate_for_study
+from optimization_engine.processors.surrogates.neural_surrogate import create_parametric_surrogate_for_study
 
 print("Testing Parametric Neural Surrogate")
 print("=" * 60)

archive/test_scripts/test_training_data_export.py

@@ -117,7 +117,7 @@ from pathlib import Path
 # Add parent directory to path
 sys.path.insert(0, str(Path(__file__).parent.parent.parent))
 
-from optimization_engine.runner import OptimizationRunner
+from optimization_engine.core.runner import OptimizationRunner
 
 def main():
     """Run the optimization."""