feat: Complete Phase 3 - pyNastran Documentation Integration

Phase 3 implements automated OP2 extraction code generation using
pyNastran documentation research. This completes the zero-manual-coding
pipeline for FEA optimization workflows.

Key Features:
- PyNastranResearchAgent for automated OP2 code generation
- Documentation research via WebFetch integration
- 3 core extraction patterns (displacement, stress, force)
- Knowledge base architecture for learned patterns
- Successfully tested on real OP2 files

Phase 2.9 Integration:
- Updated HookGenerator with lifecycle hook generation
- Added POST_CALCULATION hook point to hooks.py
- Created post_calculation/ plugin directory
- Generated hooks integrate seamlessly with HookManager

New Files:
- optimization_engine/pynastran_research_agent.py (600+ lines)
- optimization_engine/hook_generator.py (800+ lines)
- optimization_engine/inline_code_generator.py
- optimization_engine/plugins/post_calculation/
- tests/test_lifecycle_hook_integration.py
- docs/SESSION_SUMMARY_PHASE_3.md
- docs/SESSION_SUMMARY_PHASE_2_9.md
- docs/SESSION_SUMMARY_PHASE_2_8.md
- docs/HOOK_ARCHITECTURE.md

Modified Files:
- README.md - Added Phase 3 completion status
- optimization_engine/plugins/hooks.py - Added POST_CALCULATION hook

Test Results:
- Phase 3 research agent: PASSED
- Real OP2 extraction: PASSED (max_disp=0.362mm)
- Lifecycle hook integration: PASSED

Generated with Claude Code

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

optimization_engine/plugins/hooks.py

@@ -20,6 +20,7 @@ class HookPoint(Enum):
     PRE_SOLVE = "pre_solve"         # Before solver execution
     POST_SOLVE = "post_solve"       # After solve, before extraction
     POST_EXTRACTION = "post_extraction"  # After result extraction
+    POST_CALCULATION = "post_calculation"  # After inline calculations (Phase 2.8), before reporting
     CUSTOM_OBJECTIVE = "custom_objective"  # Custom objective functions