World: baked splat ground — unique multi-texture base per biome, path/arena wear baked in, HP detail layer

Second ground iteration ("better but could be further improved"): the remaining
plainness was single-texture ground — noise only modulated brightness, never
MATERIAL. Now each biome bakes a unique 1024 splat-blended base map (zero
repetition at macro scale) with the fine texture moved to the detail slot as a
high-pass layer at real tiling:

- Meadow: grass + dirt + clover patches masked by fbm; the worn paths
  (storage->warpgate, storage->base-gate) and a congregation-wear disc at the
  storage crystal are baked INTO the splat as organic dirt zones (exact
  plane-UV mapping probed: u=0.5-x/90 — both axes inverted).
- Arid: sand + sand2 + arid-dirt patches + a subtle arena-wear disc at the
  quad center (= the room origin on both quads) + warm/cool hue drift.
- Detail slot: generated 2048 high-pass (full - 128-blur, 1.4x) of the
  grass/sand textures, LINEAR import, tiled 22x/26x — crisp up close, the
  splat carries identity at distance.
- Superseded assets removed: the overlay WornPath quads + material + texture
  (double-darkened over the baked wear and caught fog as a ghostly rectangle)
  and the old macro-noise detail textures.

Biome tint MPB + normals unchanged and still active. Measured ground luminance
0.30/0.33 (edit ambient) — play fog/dark ambient pulls it down; tints remain
the one-line brightness knob.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Assets/_Project/Materials/Mat_Ground_Arid_Dark.mat

@@ -41,16 +41,16 @@ Material:
     serializedVersion: 3
     m_TexEnvs:
     - _BaseMap:
-        m_Texture: {fileID: 2800000, guid: c27220858ae0f6446aad43a6e7176710, type: 3}
-        m_Scale: {x: 26, y: 26}
+        m_Texture: {fileID: 2800000, guid: dd6cb7f94d22cca4485f43c54224764d, type: 3}
+        m_Scale: {x: 1, y: 1}
         m_Offset: {x: 0, y: 0}
     - _BumpMap:
         m_Texture: {fileID: 2800000, guid: c39c27cb220c80f40b13ba94a921d2fa, type: 3}
         m_Scale: {x: 26, y: 26}
         m_Offset: {x: 0, y: 0}
     - _DetailAlbedoMap:
-        m_Texture: {fileID: 2800000, guid: 15a6054fd7a19af41823672d9f02cf76, type: 3}
-        m_Scale: {x: 1, y: 1}
+        m_Texture: {fileID: 2800000, guid: 49ab3af8e830e8e48b579aa223cad867, type: 3}
+        m_Scale: {x: 26, y: 26}
         m_Offset: {x: 0, y: 0}
     - _DetailMask:
         m_Texture: {fileID: 0}
@@ -65,8 +65,8 @@ Material:
         m_Scale: {x: 2, y: 1}
         m_Offset: {x: 0, y: 0}
     - _MainTex:
-        m_Texture: {fileID: 2800000, guid: c27220858ae0f6446aad43a6e7176710, type: 3}
-        m_Scale: {x: 26, y: 26}
+        m_Texture: {fileID: 2800000, guid: dd6cb7f94d22cca4485f43c54224764d, type: 3}
+        m_Scale: {x: 1, y: 1}
         m_Offset: {x: 0, y: 0}
     - _MetallicGlossMap:
         m_Texture: {fileID: 0}