feat(ui): backend-aware sidebar + per-backend Family tree visualization

* Solve sidebar splits cleanly on backend: PQQA shows only PQQA knobs +
  presets; PA shows only PA knobs + a dedicated PA preset set
  (Smoke / Default / Thorough). Removes the "inactive controls"
  confusion shown in the bug report screenshot.
* PA dynamics chart split into stacked subplots so Loss and ESS no
  longer overlap; ESS panel pins R as a dashed Kish-ceiling guideline.
* Visualize: "PA: Family tree" -> backend-agnostic "Family tree" tab.
  PA branch keeps the Muller plot + sorted ancestry + survivor curve;
  PQQA branch shows a hierarchical-clustering dendrogram of the final
  population plus per-clade energy trajectory bands (mode-collapse
  pseudo-genealogy).
* AppTest regressions: assert PQQA-only sliders never leak into the PA
  sidebar; assert "Family tree" tab is present for both backends.

Author: Yuma-Ichikawa