🎨 Palette: Enhanced CLI Output and Input Validation

[EiJackGH]

• 💡 What:
  • Added comprehensive input validation for all CLI arguments.
  • Fixed a bug where --quiet mode still printed trade events and double headers.
  • Overhauled the Final Portfolio Performance report with a structured ASCII table, ROI %, Buy & Hold comparison, and accurate trade statistics.
  • Consolidated duplicate Colors class definitions.
• 🎯 Why: To make the CLI tool more robust, user-friendly, and informative. The previous output was redundant and lacked key performance metrics.
• ♿ Accessibility: Added clear error messages and ensured --no-color works correctly by fixing the Colors class.

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PR created automatically by Jules for task 15083254635589535245 started by @EiJackGH

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