feat(tools): irregular strata and angular boulder blocks

Strata gain a dip, a slow seeded warp that bends and notches the beds, and
a per-bed thickness and hardness jitter with ordered boundaries, so walls
never invert. BoulderField gains an angularity parameter: elongated
super-ellipse slabs with flat tops, sharp shoulders, random heading and
tilt, footprint area preserved. Both sites are re-baked with the new
settings; the coral heads stay rounded.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

tools/sites/zone1_vigilant_recipe.gd

@@ -75,7 +75,10 @@ static func recipe() -> SiteTerrainBaker.Recipe:
 		# Crumbly rock on every slope steeper than the sand rule, smooth sand elsewhere.
 		# Before the strata so the ledges stay flat.
 		SiteTerrainBaker.SlopeRoughness.new(1935, 0.12, 0.7, 20.0, 40.0),
-		SiteTerrainBaker.Strata.new(4.0, 0.85, 25.0, 40.0, Rect2(-384.0, STRATA_START_Z, 768.0, 384.0 - STRATA_START_Z)),
+		SiteTerrainBaker.Strata.new(
+			4.0, 0.85, 25.0, 40.0, Rect2(-384.0, STRATA_START_Z, 768.0, 384.0 - STRATA_START_Z),
+			Vector2(0.008, 0.0), 1938, 2.0, 0.45
+		),
 	]
 	result.material_patches = [
 		SiteTerrainBaker.MaterialPatch.new(Vector2(140.0, 40.0), 28.0, SonarMaterial.Value.ROCK),