Add DCTP (Delta Code Transfer Protocol) tool for efficient AI code transfers

DCTP enables efficient transfer of AI-generated code using delta operations
instead of sending complete files for each modification. Features include:

- Parser for DCTP control commands (NEW, DELETE, INSERT_AFTER, REPLACE, RENUMBER)
- Line-numbered code with language-specific comment formats
- Backup/Undo system with session management
- Diff generation for preview functionality
- CustomTkinter GUI with project management, preview, and diff views

dctp/.gitignore

@@ -0,0 +1,5 @@
+__pycache__/
+*.pyc
+*.pyo
+.dctp_backups/
+.dctp_settings.json