get_net_connections() previously required wire segments between net
labels and component pins. If a label was placed exactly at a pin
endpoint (no wire), the net was silently dropped and generate_netlist
returned 0 nets.
Fix: build all_match_points as the union of connected wire endpoints
and label positions. Pin matching now checks both, so label-at-pin
schematics (valid KiCad style) produce correct netlists alongside
traditional wired schematics.
00a59a590b