chore: Project cleanup and Canvas UX improvements (Phase 7-9)

## Cleanup (v0.5.0)
- Delete 102+ orphaned MCP session temp files
- Remove build artifacts (htmlcov, dist, __pycache__)
- Archive superseded plan docs (RALPH_LOOP V2/V3, CANVAS V3, etc.)
- Move debug/analysis scripts from tests/ to tools/analysis/
- Archive redundant NX journals to archive/nx_journals/
- Archive monolithic PROTOCOL.md to docs/archive/
- Update .gitignore with missing patterns
- Clean old study files (optimization_log_old.txt, run_optimization_old.py)

## Canvas UX (Phases 7-9)
- Phase 7: Resizable panels with localStorage persistence
  - Left sidebar: 200-400px, Right panel: 280-600px
  - New useResizablePanel hook and ResizeHandle component
- Phase 8: Enable all palette items
  - All 8 node types now draggable
  - Singleton logic for model/solver/algorithm/surrogate
- Phase 9: Solver configuration
  - Add SolverEngine type (nxnastran, mscnastran, python, etc.)
  - Add NastranSolutionType (SOL101-SOL200)
  - Engine/solution dropdowns in config panel
  - Python script path support

## Documentation
- Update CHANGELOG.md with recent versions
- Update docs/00_INDEX.md
- Create examples/README.md
- Add docs/plans/CANVAS_UX_IMPROVEMENTS.md

tools/analysis/check_api_routes.py

@@ -0,0 +1,20 @@
+"""Check API routes from running backend."""
+import requests
+import json
+
+# Get OpenAPI spec
+resp = requests.get("http://localhost:8000/openapi.json", timeout=10)
+spec = resp.json()
+
+# Find insight routes
+print("Insight-related routes:")
+print("=" * 60)
+for path in sorted(spec.get("paths", {}).keys()):
+    if "insight" in path.lower():
+        print(f"  {path}")
+
+print()
+print("All routes:")
+print("-" * 60)
+for path in sorted(spec.get("paths", {}).keys()):
+    print(f"  {path}")