Identify and document missing opt_passive inputs blocking three-regime finalization

[Copilot]

This issue was intended to finalize the study as a clean three-controller relay — CC → opt_passive → ff+PID — entirely in --plot-only mode from committed CSVs, while pruning the degenerate fixed-passive arm. Repository inspection showed the required analysis/opt_passive/*.csv inputs are not actually present in the merged state, so the three-regime regeneration path cannot be completed honestly from committed data.

• What this branch establishes

  • Unshallow repository history and verify the passive-study merge contents.
  • Confirm analysis/cc/ and analysis/passive_guarded/ contain committed sweep CSVs.
  • Confirm analysis/opt_passive/ contains only figures, not the committed capture-efficiency CSVs required by the issue.
  • Confirm the existing opt_passive figures are placeholder/denominator-only outputs rather than recoverable captured-power data.

• Why this matters

  • The requested cleanup depends on --plot-only regeneration from committed CSVs.
  • The three-regime overlays, regime-band shading, cross-flap summaries, and operating-envelope hull all require the missing opt_passive capture data.
  • Pruning passive without restoring the missing opt_passive inputs would leave the study unreproducible.

• Observed repository state

  analysis/cc/capture_efficiency_VGM{0,10,20,45,90}.csv
  analysis/passive_guarded/capture_efficiency_VGM{0,10,20,45,90}.csv
  
  analysis/opt_passive/figures/capture_efficiency_VGM0.png
  analysis/opt_passive/figures/capture_efficiency_VGM10.png
  analysis/opt_passive/figures/capture_efficiency_VGM20.png
  analysis/opt_passive/figures/capture_efficiency_VGM45.png
  analysis/opt_passive/figures/capture_efficiency_VGM90.png
  # no analysis/opt_passive/capture_efficiency_VGM*.csv

• Follow-up needed before the final cleanup PR

  • Restore or commit analysis/opt_passive/capture_efficiency_VGM{0,10,20,45,90}.csv.
  • Then rebase the study around the three-regime comparison and prune the fixed-passive outputs.