Port Legacy-style Star Fissures age feature (#58)

src/main/resources/data/rivencraft/rivencraft/symbols/feature/star_fissures.json

@@ -0,0 +1,8 @@
+{
+  "schema_version": 2,
+  "name": "symbol.rivencraft.feature.star_fissures",
+  "description": "symbol.rivencraft.feature.star_fissures.description",
+  "category": "rivencraft:feature",
+  "semantics": { "role": "feature", "value": "rivencraft:star_fissures" },
+  "poem": "Star Fissure World Home"
+}