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.

nautilus_dolphin/dolphin_paths.py

@@ -0,0 +1,64 @@
+"""
+Platform-independent path resolution for DOLPHIN systems.
+
+CONFIRMED PATH INVENTORY (2026-03-17):
+  Win: C:\\Users\\Lenovo\\Documents\\- Dolphin NG HD (NG3)\\correlation_arb512
+  Lin: /mnt/ng6_data          ← SMB share DolphinNG6_Data
+       /mnt/ng6_data/eigenvalues  ← eigenfiles + ExF, per-date subdirs
+
+  Win: C:\\Users\\Lenovo\\Documents\\- DOLPHIN NG HD HCM TSF Predict
+  Lin: /mnt/dolphin            ← SMB share DolphinNG5_Predict
+       /mnt/dolphin/vbt_cache        ← VBT vector cache, Parquet, ~1.7K files, 5yr
+       /mnt/dolphin/vbt_cache_klines ← 5yr klines, 1m resolution, Parquet
+       /mnt/dolphin/arrow_backfill   ← 5yr Arrow + synthetic backfill data
+
+Usage:
+    from dolphin_paths import (
+        get_arb512_storage_root,
+        get_eigenvalues_path,
+        get_project_root,
+        get_vbt_cache_dir,
+        get_klines_dir,
+        get_arrow_backfill_dir,
+    )
+"""
+import sys
+from pathlib import Path
+
+# ── Windows base paths ────────────────────────────────────────────────────────
+_WIN_NG3_ROOT   = Path(r"C:\Users\Lenovo\Documents\- Dolphin NG HD (NG3)\correlation_arb512")
+_WIN_PREDICT    = Path(r"C:\Users\Lenovo\Documents\- DOLPHIN NG HD HCM TSF Predict")
+
+# ── Linux mount points ────────────────────────────────────────────────────────
+_LIN_NG6_DATA   = Path("/mnt/ng6_data")   # DolphinNG6_Data  → correlation_arb512
+_LIN_DOLPHIN    = Path("/mnt/dolphin")    # DolphinNG5_Predict → HCM TSF Predict
+
+
+def get_arb512_storage_root() -> Path:
+    """correlation_arb512 root — eigenvalues, matrices, arrow_scans, metadata."""
+    return _WIN_NG3_ROOT if sys.platform == "win32" else _LIN_NG6_DATA
+
+
+def get_eigenvalues_path() -> Path:
+    """Eigenfiles + ExF per-date subdirs."""
+    return get_arb512_storage_root() / "eigenvalues"
+
+
+def get_project_root() -> Path:
+    """DOLPHIN NG HD HCM TSF Predict root (Predict / VBT / Alpha Engine)."""
+    return _WIN_PREDICT if sys.platform == "win32" else _LIN_DOLPHIN
+
+
+def get_vbt_cache_dir() -> Path:
+    """VBT vector cache — Parquet, ~1.7K files, 5yr history."""
+    return get_project_root() / "vbt_cache"
+
+
+def get_klines_dir() -> Path:
+    """5yr klines data — 1m resolution, Parquet, backtesting."""
+    return get_project_root() / "vbt_cache_klines"
+
+
+def get_arrow_backfill_dir() -> Path:
+    """~5yr Arrow format + DOLPHIN synthetic backfill data."""
+    return get_project_root() / "arrow_backfill"