feat(charting): unify configurable time windows

backend/tests/test_prometheus_range.py

@@ -14,16 +14,33 @@ from media_library_viewer_api.widgets.prometheus_range import (
 
 
 class TestStepForWindow:
-    """SC-104: every preset must yield 100–300 points."""
+    """SC-104: presets preserve usable resolution without sub-15s steps."""
 
     @pytest.mark.parametrize("preset", sorted(WINDOW_PRESETS))
-    def test_presets_yield_in_band_point_counts(self, preset: str) -> None:
+    def test_presets_yield_supported_point_counts(self, preset: str) -> None:
         window = WINDOW_PRESETS[preset]
         step = step_for_window(window)
-        # Clamped minimum.
+        # The Prometheus-safe 15-second floor limits the two short presets to
+        # 20 and 60 points; all longer windows stay in the 100–300 target band.
         assert step >= 15
         point_count = window // step
-        assert 100 <= point_count <= 300, f"{preset}: {point_count} points (step={step})"
+        assert min(100, window // 15) <= point_count <= 300, f"{preset}: {point_count} points (step={step})"
+
+    def test_window_presets_cover_the_shared_chart_windows(self) -> None:
+        assert WINDOW_PRESETS == {
+            "5m": 300,
+            "15m": 900,
+            "30m": 1_800,
+            "1h": 3_600,
+            "3h": 10_800,
+            "6h": 21_600,
+            "12h": 43_200,
+            "24h": 86_400,
+            "2d": 172_800,
+            "7d": 604_800,
+            "14d": 1_209_600,
+            "30d": 2_592_000,
+        }
 
     def test_floor_of_fifteen_seconds(self) -> None:
         # A tiny window that would otherwise produce a sub-15s step is clamped.