Prepare minimum submission bundle

submit/final/adapter/coordinates.py

@@ -0,0 +1,26 @@
+"""Coordinate constructors; no feature aggregation happens here."""
+from __future__ import annotations
+
+import numpy as np
+
+
+def physical_targets(duration_s: float, steps: int) -> np.ndarray:
+    """K fixed bins spanning verified real media duration, in seconds."""
+    duration = float(duration_s)
+    if not np.isfinite(duration) or duration <= 0 or steps < 1:
+        raise ValueError("physical targets require positive finite duration and steps")
+    edges = np.linspace(0.0, duration, steps + 1, dtype=np.float64)
+    return np.column_stack((edges[:-1], edges[1:]))
+
+
+def relative_cells(length: int) -> np.ndarray:
+    """Ordered source cells on a unit progress axis, with no time claim."""
+    if length < 1:
+        raise ValueError("relative source length must be positive")
+    left = np.arange(length, dtype=np.float64) / length
+    return np.column_stack((left, left + 1.0 / length))
+
+
+def relative_targets(steps: int) -> np.ndarray:
+    """K fixed cells on the same unit progress axis."""
+    return relative_cells(steps)