v3.4.1: Better Eagle layer name detection

A minor revision that fixes how Eagle layer file names are interpreted.

Released October 15, 2026. Auto-update will deliver v3.4.1 to existing installs over the next few hours.

Some Eagle CAM jobs name their solder mask files Top_Solder_Stop_Mask and Bottom_Solder_Stop_Mask. GerbDiff read both as the top solder mask, so the bottom mask could not be compared between revisions. That is fixed, and several other Eagle names, such as Top_Cream, Bot_Silk_Screen and Copper_InnerTop, are now recognized as their proper layers.

Thanks to the user who reported this and sent files to reproduce it.