Merge verification-harness — D-239 tile-derivation harness (T-1031, closes T-974)

server/src/atlas/region_profile.rs

@@ -496,7 +496,7 @@ pub fn derive_river_threshold(tectonic: TectonicClass, precip: PrecipitationClas
 ///   - BraidedPlain (§6) is NOT emitted at region scale — distinguishing it from Delta needs a lithology signal (§8 Gravel→braided) RegionProfile lacks; deferred to ChunkContext (see the D-239 §6 implementation note).
 ///
 /// D-010: all gates are integer comparisons. No float arithmetic in this function.
-fn derive_morphology_zone(
+pub fn derive_morphology_zone(
     tectonic: TectonicClass,
     glaciation: GlaciationGrade,
     slope_q: i32,

server/tests/golden/derivation_harness.json

@@ -0,0 +1,38 @@
+[
+  {
+    "label": "alluvial_forest_active_channel",
+    "seed": 16045690984503098046,
+    "body_id": "GJ144d",
+    "tile_x": 640,
+    "tile_y": 1280,
+    "terrain": 0,
+    "vegetation": 1,
+    "water": 0,
+    "elevation_m": 11,
+    "cover": 0
+  },
+  {
+    "label": "lava_field_barren",
+    "seed": 1311768467294899695,
+    "body_id": "GJ581c",
+    "tile_x": 320,
+    "tile_y": 448,
+    "terrain": 5,
+    "vegetation": 0,
+    "water": 0,
+    "elevation_m": 21,
+    "cover": 0
+  },
+  {
+    "label": "fjord_wall_glaciated",
+    "seed": 18369614217980264670,
+    "body_id": "GJ447c",
+    "tile_x": 928,
+    "tile_y": 544,
+    "terrain": 3,
+    "vegetation": 0,
+    "water": 2,
+    "elevation_m": 1,
+    "cover": 1
+  }
+]