Fix: Handle invalid color formats and style errors gracefully - #5765

Summary

This PR fixes two related issues:

Fixes #2922

Uncaught exception when using --user-input-color with wrong format (e.g., missing # prefix like 'bcbdbf').

Fixes #2962

Uncaught MissingStyle error when choosing 'A' when prompted to add many files to the chat ('ansigray' style issue).

Changes Made

1. Improved color validation ():

   • Added to the list of caught exceptions alongside to properly handle invalid hex color strings without # prefixes
   • Now gracefully disables invalid colors instead of crashing

2. Added style error fallback in all console output methods:

   • : Wrapped console.print in try/except to fall back to unstyled output if style fails
   • : Same error handling for tool output with colors
   • : Added outer try/except to catch any style-related errors and fall back to plain text
   • : Added try/except around Markdown rendering to handle any style errors gracefully

Testing

• Invalid color formats now show a warning instead of crashing
• Any style application errors during output now gracefully fall back to plain unstyled text
• All existing functionality remains intact