Patch Release - Performance and Stability Improvement

Maintenance release addressing file modification tracking issues and improving application stability.
This release is a culmination of multiple commits related to performance, stability and overall app experience after getting feedback.

Fixed

• Critical: File modification indicator (asterisk) now correctly reflects document state after save operations
• Critical: Spurious textChanged signals during file load no longer trigger false modification state
• Critical: Document modification state properly synchronized between Qt's internal tracking and application UI
• File save operations no longer cause immediate re-marking of files as modified
• New file creation no longer incorrectly marks files as modified before any edits
• Editor tab titles now accurately reflect saved/unsaved state without manual intervention

Added

Documentation:

• TROUBLESHOOTING.md with Wine compatibility guidance and common issue resolution
• Wine/Linux limitations documented with source installation instructions
• README.md updated with platform compatibility warnings

Changed

• Problems table now read-only to prevent accidental edits while preserving copy functionality
• All program types now execute in external terminal windows for consistent I/O behavior
• File modification tracking migrated to Qt's QTextDocument.isModified() for reliable state management
• Signal-based architecture for modification state changes using custom pyqtSignal

Performance Improvements

• Trie-based syntax highlighting for O(n) keyword matching instead of O(n*m) regex operations
• LRU cache on toolchain detection for faster repeated lookups
• Debounced syntax highlighting with 200ms delay to reduce CPU usage during rapid typing
• Precompiled regex patterns for string and comment matching
• Optimized highlightBlock() implementation reducing editor lag on large files

Technical Improvements

• Implemented proper signal blocking during file load operations to prevent false positives
• Added _loading flag to distinguish between programmatic and user-initiated text changes
• Modified save_file() to explicitly set document modification state via setModified(False)
• Refactored _on_text_changed() to check document.isModified() as source of truth
• Disconnection and reconnection of textChanged signal during file loading for clean state initialization
• FastSyntaxHighlighter class with TrieNode data structure for efficient keyword lookup

Known Issues

• Windows-only distribution (Wine compatibility not supported for PyInstaller builds)
• Large size of the app folder