refactor: use zcm.Multiscales typed model per reviewer feedback

- Replace dict[str, Any] multiscales field with zcm.Multiscales import
- Remove inline MultiscalesTransform/ScaleLevel/Multiscales classes
- Update test assertions for Pydantic model attribute access

Author: emmanuelmathot

src/eopf_geozarr/data_api/s1_rtc.py

@@ -15,16 +15,16 @@
     ├── ascending/
     │   ├── zarr.json          # zarr_conventions, multiscales, proj:, spatial:
     │   ├── r10m/              # native resolution dataset
-    │   │   ├── vv/            # (time, y, x) float32
-    │   │   ├── vh/            # (time, y, x) float32
-    │   │   ├── border_mask/   # (time, y, x) uint8
+    │   │   ├── vv/            # (time, Y, X) float32
+    │   │   ├── vh/            # (time, Y, X) float32
+    │   │   ├── border_mask/   # (time, Y, X) uint8
     │   │   ├── time/          # (time,) int64 datetime
     │   │   ├── absolute_orbit/
     │   │   ├── relative_orbit/
     │   │   └── platform/
     │   ├── r20m/ … r720m/     # overview levels (vv, vh, border_mask only)
     │   └── conditions/
-    │       └── gamma_area_{orbit}/  # (y, x) float32
+    │       └── gamma_area_{orbit}/  # (Y, X) float32
     └── descending/
         └── (same structure)
 """
@@ -40,6 +40,7 @@
 from zarr_cm import spatial as spatial_cm
 
 from eopf_geozarr.data_api.geozarr.common import DatasetAttrs
+from eopf_geozarr.data_api.geozarr.multiscales.zcm import Multiscales
 from eopf_geozarr.pyz.v3 import ArraySpec, GroupSpec
 
 # ============================================================================
@@ -61,33 +62,6 @@
 # ============================================================================
 
 
-class MultiscalesTransform(BaseModel):
-    """Scale/translation transform between resolution levels."""
-
-    scale: tuple[float, ...] | None = None
-    translation: tuple[float, ...] | None = None
-
-
-class MultiscalesScaleLevel(BaseModel):
-    """A single resolution level in the multiscales layout."""
-
-    asset: str
-    derived_from: str | None = None
-    transform: MultiscalesTransform | None = None
-    resampling_method: str | None = None
-
-    model_config = {"extra": "allow"}
-
-
-class Multiscales(BaseModel):
-    """Typed multiscales metadata (layout + optional resampling_method)."""
-
-    layout: tuple[MultiscalesScaleLevel, ...]
-    resampling_method: str | None = None
-
-    model_config = {"extra": "allow"}
-
-
 class S1RtcOrbitGroupAttrs(BaseModel):
     """Attributes for an orbit-direction group (ascending or descending).
 
@@ -167,7 +141,7 @@ class S1RtcConditionsAttrs(BaseModel):
 class S1RtcNativeResolutionMembers(TypedDict, closed=True, total=False):  # type: ignore[call-arg]
     """Members for the native resolution dataset (r10m).
 
-    Data variables (time, y, x) plus 1-D coordinate variables (time,).
+    Data variables (time, Y, X) plus 1-D coordinate variables (time,).
     All fields optional since not all arrays are present during incremental construction.
     """
 
@@ -301,9 +275,9 @@ class S1RtcRoot(GroupSpec[DatasetAttrs, S1RtcRootMembers]):  # type: ignore[type
         ├── ascending/
         │   ├── zarr.json          # zarr_conventions, multiscales, proj:, spatial:
         │   ├── r10m/
-        │   │   ├── vv/            # (time, y, x) float32
-        │   │   ├── vh/            # (time, y, x) float32
-        │   │   ├── border_mask/   # (time, y, x) uint8
+        │   │   ├── vv/            # (time, Y, X) float32
+        │   │   ├── vh/            # (time, Y, X) float32
+        │   │   ├── border_mask/   # (time, Y, X) uint8
         │   │   ├── time/          # (time,) int64
         │   │   ├── absolute_orbit/
         │   │   ├── relative_orbit/

tests/test_data_api/test_s1_rtc.py

@@ -76,9 +76,8 @@ def test_s1_rtc_orbit_attrs(s1_rtc_json_example: dict[str, object]) -> None:
     assert attrs.proj_code.startswith("EPSG:")
     assert attrs.spatial_dimensions == ["y", "x"]
     assert len(attrs.spatial_bbox) == 4
-    layout = attrs.multiscales["layout"]
-    assert len(layout) == 6
-    assert layout[0]["asset"] == "r10m"
+    assert len(attrs.multiscales.layout) == 6
+    assert attrs.multiscales.layout[0].asset == "r10m"
 
 
 def test_s1_rtc_rejects_no_orbit(s1_rtc_json_example: dict[str, object]) -> None: