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.

.gitignore

@@ -1,27 +1,18 @@
-# Python
-__pycache__/
-*.py[oc]
-build/
-dist/
-wheels/
-*.egg-info
-
-# Virtual environments
-.venv
-
-# UV
-uv
-uv.lock
+# Rust
+target/
 
 # Captures (binary data, not tracked)
 captures/
 
-# Lamp export bundles (published to the website repo instead)
+# left over from the Python tools
+__pycache__/
+*.py[oc]
+.venv
+uv
+uv.lock
 lamps/
 
-# Claude Code
-.claude/
-
 # Local AI-tooling state
+.claude/
 .claude-flow/
 .swarm/