Add post-processing tool: clean and plot CSV data

hioki-clean clean <file> - removes error rows and settle artifacts
after auto-range transitions. hioki-clean plot <file> - visualizes
CSV data with grouped subplots (voltage, current, power, efficiency).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

uv.lock

@@ -121,7 +121,7 @@ wheels = [
 [[package]]
 name = "hioki-3193"
 version = "0.1.0"
-source = { virtual = "." }
+source = { editable = "." }
 dependencies = [
     { name = "matplotlib" },
     { name = "pyvisa" },