Add shade profiles, 2D V×I sweep, meter format toggle, ON/OFF indicators, and GUI console

- Shade profile: CSV-driven irradiance/voltage sequences with load control
  (bench.run_shade_profile, CLI shade-profile command, GUI profile panel)
- 2D sweep: voltage × load current efficiency map with live graph updates
  (bench.sweep_vi, CLI sweep-vi command, GUI sweep panel with background thread)
- GUI: meter format selector (scientific/normal), supply/load ON/OFF indicators,
  console log with stdout redirect and color-coded messages
- Sample profiles: cloud_pass, partial_shade, intermittent_clouds

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

samples/cloud_pass.csv

@@ -0,0 +1,11 @@
+time,voltage,current_limit,load_mode,load_value
+0,75,10.0,CC,3.0
+10,75,8.0,CC,3.0
+20,75,6.0,CC,3.0
+30,75,4.0,CC,2.0
+40,75,2.0,CC,1.0
+50,75,2.0,CC,1.0
+60,75,4.0,CC,2.0
+70,75,6.0,CC,3.0
+80,75,8.0,CC,3.0
+90,75,10.0,CC,3.0

samples/intermittent_clouds.csv

@@ -0,0 +1,15 @@
+time,voltage,current_limit,load_mode,load_value
+0,75,10.0,CC,3.0
+10,75,10.0,CC,3.0
+15,75,4.0,CC,2.0
+25,75,4.0,CC,2.0
+30,75,10.0,CC,3.0
+40,75,10.0,CC,3.0
+45,75,6.0,CC,2.5
+55,75,6.0,CC,2.5
+60,75,10.0,CC,3.0
+70,75,10.0,CC,3.0
+75,75,2.0,CC,1.0
+90,75,2.0,CC,1.0
+95,75,10.0,CC,3.0
+110,75,10.0,CC,3.0

samples/partial_shade.csv

@@ -0,0 +1,11 @@
+time,voltage,current_limit,load_mode,load_value
+0,75,10.0,CC,3.0
+15,75,10.0,CC,3.0
+30,75,7.0,CC,3.0
+45,65,5.0,CC,2.5
+60,55,3.0,CC,2.0
+75,55,3.0,CC,2.0
+90,65,5.0,CC,2.5
+105,75,7.0,CC,3.0
+120,75,10.0,CC,3.0
+135,75,10.0,CC,3.0