Conditionalize Dircon Rouvy compatibility features to rouvy_compatibility flag

[cagnulein]

#4138

This commit ensures that all Rouvy-specific protocol changes are properly conditioned to the rouvy_compatibility flag, restoring original behavior when the flag is disabled.

Changes:

• dirconmanager.cpp: Remove hardcoded INDICATE flag from 0x2AD9 characteristics, add conditional logic to apply INDICATE only when rouvy_compatibility is true
• dirconpacket.h: Add rouvy_compatibility parameter to parse() and encode() methods
• dirconpacket.cpp: Conditionalize relaxed validation (>= vs ==) and 0x07 message handling to rouvy_compatibility flag
• dirconprocessor.cpp: Conditionalize INDICATE flag check and pass rouvy_compatibility to all parse()/encode() calls

Result: Complete backward compatibility when rouvy_compatibility=false