PyVizAST Prerelease 0.7.0-rc3

Bug Fixes & Performance Optimizations

Backend Fixes:

• Fixed async sync blocking in projects.py: Added run_in_executor for file I/O and AST parsing operations
• Fixed incomplete exception handling in parser.py: Added MemoryError catch with smart truncation
• Fixed redundant AST traversal in node_builder.py: Combined 3 separate ast.walk calls into single pass for 3x performance improvement
• Fixed lint errors (F541, F821, F401) across multiple files

Frontend Improvements:

• Enhanced CodeEditor.js for large file performance:
  • Disabled minimap for files > 3000 lines
  • Disabled folding for files > 5000 lines
  • Added performance warning banner for large files
  • Improved memory management for very large files
• Confirmed proper cleanup in useResizeObserver.js, GestureService.js, and ASTVisualizer3D.js

Performance:

• node_builder.py: _count_code_elements() now does single traversal instead of 3
• Reduced memory usage for large file editing
• Better error handling for edge cases

Files Modified:

• backend/routers/projects.py - Async file operations
• backend/ast_parser/parser.py - MemoryError handling
• backend/ast_parser/node_builder.py - Performance optimization
• frontend/src/components/CodeEditor.js - Large file handling
• frontend/src/components/components.css - Performance warning styles