when used to show a single cell, do an automatic zoom on pageload

[mattvenn]

for example, when I load this cell, it's very small and in the corner.

https://gds-viewer.tinytapeout.com/?model=https://tinytapeout.github.io/sky130B-cells-gltf/cells/sky130_fd_sc_hd__inv_1.gds.gltf

[urish]

Fixed by #10