AC mains might be fused at 16A, while our dual-layer 3.81mm traces
don't really sustain more than 10A (assuming 35u copper). Let's
fuse by default with 6.3A which is fine for any heating up to 1.4kW.
In my use case the heating has 70W or 300W, so I could even fuse lower.
LTS418S: Enlarge solder pad length to simplify hand soldering
The original footprint is designed for solder paste / reflow.
For hand-soldering with an iron, longer pads make the task a bit
simpler. Length is only elongated outside of the package, so
insulation clearance is unaffected.