docs: fixed the image for the kicad sim settings, it was truncated for some reason

docs: updated intro docs to make note about KiCad simulation compatibility settings and also added a note about it being fort KiCad 7 only at the moment, also also added alt text for all the images missing it

docs: another small fix

docs: fixed a typo

docs: revamped the introduction

examples: Added a sky130 CMOS Inverter Example

fixup!: fixed the indexing of the fet pins

contrib: fixed the pin-ordering for the primitive FETs, I did a programmer brain of starting from 0 not 1

symbols: sky130B: regenerated PDK libs, includes fundamental FET symbols now

symbols: sky130A: regenerated PDK libs, includes fundamental FET symbols now

contrib: removed an accidental inclusion of a debug print

symbols: spice: Added the FET shim to allow for KiCad SPICE sim of single sky130 transistors

contrib: Added special shim to insert the standard sky130 fets into the `sky130_fd_pr` cell library

contrib: ext: patched the LEF parser a bit because `sky130_fd_io` uses `<\d>` for it's bus index naming unlike every other cell library, but also is technicaly invalid because the LEF still only specifies that `[\d]` is used :v

docs: updated regen docs to account for the change in SPICE merge flag behavior