initial: import DOLPHIN baseline 2026-04-21 from dolphinng5_predict working tree

Includes core prod + GREEN/BLUE subsystems:
- prod/ (BLUE harness, configs, scripts, docs)
- nautilus_dolphin/ (GREEN Nautilus-native impl + dvae/ preserved)
- adaptive_exit/ (AEM engine + models/bucket_assignments.pkl)
- Observability/ (EsoF advisor, TUI, dashboards)
- external_factors/ (EsoF producer)
- mc_forewarning_qlabs_fork/ (MC regime/envelope)

Excludes runtime caches, logs, backups, and reproducible artifacts per .gitignore.

Observability/TUI/_widgets_check.py

@@ -0,0 +1,4 @@
+import textual.widgets as w, textual.containers as c
+print("textual version:", __import__("textual").__version__)
+print("WIDGETS:", sorted([x for x in dir(w) if x[0].isupper()]))
+print("CONTAINERS:", sorted([x for x in dir(c) if x[0].isupper()]))