The ornamental design for a forward lightingsystem, as shown and described.
FIG. 1 includes a perspective view of a forward lighting system.
FIG. 2 includes a front view thereof.
FIG. 3 includes a back view thereof.
FIG. 4 includes a side view thereof.
FIG. 5 includes a bottom view thereof.
FIG. 6 includes a top view thereof; and,
FIG. 7 includes a perspective view of a firearm with a forward lighting system.
The broken lines in the figures depict portions of the forward lighting system that form no part of the claimed design. The broken line depiction of a rifle in FIG. 7 forms no part of the claimed design.