MXP Self-Healing Recovery Mechanism

Summary

This PR implements an automatic detection and recovery system for malformed MXP (Mud eXtension Protocol) parsing issues that cause screen output to freeze, addressing GitHub issue #7896.

Problem

MUDs often send improperly formatted MXP tags with unescaped characters (<, >, &) that cause Mudlet’s MXP parser to get stuck in infinite loops, freezing screen output. This particularly affects new players connecting to MUDs with problematic MXP implementations.

Solution

Error Detection

Tracks consecutive failed MXP parsing attempts
Triggers recovery mechanism after 1000 failed attempts
Captures problematic content for user display

Self-Healing Dialog

User-friendly dialog explaining the issue
Shows sample of problematic content
Three recovery options:
- Disable MXP (recommended) - Turns off MXP processing
- Continue with MXP - Resets error state, keeps MXP enabled
- Not Now - Dismisses dialog without changes

Automatic Recovery

Seamless fallback to text processing when MXP is disabled
Prevents screen output freezing
Maintains profile settings for future sessions

Technical Details

Error Detection Logic

if (!mMxpTagBuilder.accept(ch) && mMxpTagBuilder.isInsideTag() && !mMxpTagBuilder.hasTag()) {
    mTagStuckCounter++;
    mProblematicContent += ch;
    
    if (mTagStuckCounter > 1000) {
        // Trigger recovery mechanism
    }
}

Recovery Integration

The recovery system integrates into the main MXP processing loop in TBuffer.cpp, checking for stuck parsing and presenting the recovery dialog when issues are detected.

Testing

Tested with various malformed MXP scenarios:

Unescaped < and > characters in ASCII art
Incomplete MXP tags (e.g., <font color=red without closing >)
Mixed problematic content with valid MXP
Recovery dialog functionality and user option handling

Benefits

Prevents Screen Freezing - No more stuck MXP parsing blocking game output
User-Friendly - Clear explanation and recovery options
Backward Compatible - Existing MXP functionality unchanged
Minimal Disruption - Users can choose their preferred recovery method
Educational - Explains MXP issues to help user understanding

Screenshots

https://github.com/user-attachments/assets/d4a51836-0606-48b0-a228-a3a2f85a0969

Impact

This change particularly benefits new players who encounter MUDs with problematic MXP implementations, preventing the frustrating experience of frozen screen output that could drive them away from the game.

Related Issues

Fixes #7896 - Detect MXP issues and offer self-healing options

/claim #7896

Checklist

Code compiles without warnings
Functionality tested with various malformed MXP scenarios
Dialog interface tested and user-friendly
Backward compatibility maintained
No breaking changes to existing MXP functionality
Build system updated for new files