Rewrite the driver in Rust; move the testbench tools out

The repository is now only the HPCS 6500 driver: a Rust library (serial
transport, every protocol command, block parsing, USBPcap captures, a
simulated instrument) and the hpcs6500 CLI with the flags of the former
hpcs6500.py, plus dump/capture for reverse engineering.

The lamp station, lamp export, TM-30, label printer and LED calibration
move to B4L/lamp-testbench. Golden tests pin the Rust output to the Python
driver's: parsed values bit-exact, report text, CSV and number formatting.
The Python driver is at tag python-final.

tests/golden/csv_r07.txt

@@ -0,0 +1,2 @@
+timestamp,Phi_lm,eta_lm_W,CCT_K,Duv,x,y,u,v,u_prime,v_prime,SDCM,Ra,R1,R2,R3,R4,R5,R6,R7,R8,R9,R10,R11,R12,R13,R14,R15,Phi_e_mW,Phi_euv_mW,Phi_eb_mW,Phi_ey_mW,Phi_er_mW,Phi_efr_mW,Phi_eir_mW,Phi_e_total,CIE_X,CIE_Y,CIE_Z,TLCI,PeakSignal,DarkSignal,Compensate,Voltage_V,Current_A,Power_W,Freq_Hz,PF
+T,182.61920166015625,0.0,4936.84375,0.002135422546416521,0.3473931849002838,0.35774698853492737,0.21059946715831757,0.32531434297561646,0.21059946715831757,0.4879715144634247,1.5234547853469849,83.53800201416016,81.74681854248047,89.89591979980469,94.66126251220703,81.88838958740234,81.9393081665039,84.4315185546875,86.51227569580078,67.2285385131836,12.525043487548828,75.23241424560547,80.69010925292969,53.97742462158203,84.02236938476562,97.37865447998047,76.29852294921875,558.6363525390625,0.0,152.54922485351562,257.9691162109375,144.27931213378906,5.738129138946533,0.0,560.5353393554688,259.6396484375,267.3780212402344,220.3765106201172,71.05938720703125,55124.0,2518.0,2834.0,0.0,0.0,0.0,0.0,0.0