Updated injection controller

[ManojINaik]

Improved code safety and maintainability across multiple components:

• Enhanced newline encoding handling in checks.py for better cross-platform compatibility
• Modernized Windows payload construction with f-strings in tfb_payloads.py
• Optimized OS detection loop structure in controller.py
• Added input validation and error-prone string concatenation fixes
• Improved parameter validation and error handling in critical paths
• Standardized string formatting patterns for better readability

The changes improve security and reliability through:

1. Enhanced Input Validation - Strict type checking inensure_text() prevents unexpected types from causing vulnerabilities
2. Standardized String Handling - Consistent text encoding/decoding reduces manual errors in string operations
3. Cross-OS Newline Consistency - Normalized line endings ensure reliable behavior across Windows and Unix systems
4. Optimized OS Detection - More accurate platform recognition enables proper payload formatting
5. Maintainability Improvements - Clearer code structure and error handling make future updates safer