feat(lang): def REGISTRY from "file.lres" - a game fills an open registry from its own file

The entries are read and checked against the registry's record as a
registry ... from file is, errors at the resource file's line, and they
are defs of the module that wrote the line: the registry must be open to
it, and they take that module's place in the stable order. Reseed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

examples/modules/crafting/index.ludic

@@ -0,0 +1,9 @@
+# crafting/index.ludic - a registry the game may add to, and the package's own first entry
+module crafting
+export property Recipe {
+  key: string = ""
+  name: string = ""
+  minutes: int = 0
+}
+export open registry Recipes of Recipe as RC
+def Recipes rope { name: "Rope", minutes: 10 }

examples/modules/recipes.lres

@@ -0,0 +1,3 @@
+# recipes.lres - the game's own recipes, added to crafting's open registry
+tea { name: "Pine tea", minutes: 5 }
+splint { name: "Splint", minutes: 20 }

examples/modules/registry_extend.ludic

@@ -0,0 +1,12 @@
+# registry_extend.ludic — L8 + L9: a game fills a package's open registry from its own resource
+# file with `def Recipes from "recipes.lres"`. The entries are checked against Recipe as the file
+# is read, and they come after the package's own, in file order.
+#
+# Running it prints:  3 Rope Pine tea Splint 20
+import "crafting"
+program RegistryExtend {
+  def Recipes from "recipes.lres"
+  entry {
+    print(`{RC_COUNT} {Recipes[0].name} {Recipes[RC_TEA].name} {Recipes[2].name} {Recipes[recipes_find("splint")].minutes}`)
+  }
+}

examples/rejected/bad_recipes.lres

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+# bad_recipes.lres - the second entry gives minutes as text
+tea { name: "Pine tea", minutes: 5 }
+splint { name: "Splint", minutes: "twenty" }

examples/rejected/craft_kit/index.ludic

@@ -0,0 +1,8 @@
+# craft_kit/index.ludic - an open registry of recipes
+module crafting
+export property Recipe {
+  key: string = ""
+  name: string = ""
+  minutes: int = 0
+}
+export open registry Recipes of Recipe as RC

examples/rejected/registry_extend_field.ludic

@@ -0,0 +1,8 @@
+# L8 + L9: a resource file that extends a registry is checked against its record, at its own line
+import "craft_kit"
+program RegistryExtendField {
+  def Recipes from "bad_recipes.lres"
+  entry {
+    print(RC_COUNT)
+  }
+}