feat: ocean (#16)

* feat(gameplay): add Ocean biome with water generation and heightmap adjustments

- Introduce Ocean biome enum, builder, and detection logic.
- Add ocean water building to all existing biomes and modify heightmap thresholds for low mountainous areas.
- Skip cave and river generation in Ocean (and River) biomes; avoid carving water blocks.
- Comment out border blending call and update block fill logic.

* fix(gameplay): re-enable border blending and protect water in cave gen

* refactor(generation): move ocean water build to later phase

* feat(block): add is_transitional property and refine border blending

* fix(block): set stone block as transitional

* fix(world): generate temporary chunks for surface blend neighbor data

* fix(gameplay): simplify block fill logic in blend_surface_blocks_borders

* refactor(tree): remove debug logging and unused include

src/tools/math_tools.cpp

@@ -59,7 +59,12 @@ bool is_aabb_in_frustum(const glm::vec3& center, const glm::vec3& half_extents,
     }
     return true;
 }
-
+float deterministic_random(int x, int z, uint64_t seed) {
+    uint64_t h = seed;
+    h = h * 6364136223846793005ULL + (uint64_t)x;
+    h = h * 6364136223846793005ULL + (uint64_t)z;
+    return (float)(h >> 40) / (float)(1 << 24);
+}
 } // namespace Math
 
 } // namespace Cubed