Update ReflectionOfType to implement IntoString trait.

This allows for easier printing of the `reflection_of_type` macro.

Author: jemc

core/Reflection.savi

@@ -13,6 +13,10 @@
 
   :let features Array(ReflectionFeatureOfType(A)): []
 
+  :is IntoString
+  :fun into_string_space USize: @string.size
+  :fun into_string(out String'ref) None: @string.into_string(out)
+
 :class val ReflectionFeatureOfType(A)
   :let name String: ""
   :let tags Array(String): []

spec/language/semantics/reflection_spec.savi

@@ -2,10 +2,12 @@
   :fun run(test MicroTest)
     test["reflection_of_type.string String"].pass =
       (reflection_of_type "example").string == "String"
-    test["reflection_of_type.string String'ref"].pass =
-      (reflection_of_type String.new).string == "String'ref"
-    test["reflection_of_type.string Array(U8)"].pass =
-      (reflection_of_type Array(U8).new).string == "Array(U8)"
+    test["reflection_of_type string String"].pass =
+      "\(reflection_of_type "example")" == "String"
+    test["reflection_of_type string String'ref"].pass =
+      "\(reflection_of_type String.new)" == "String'ref"
+    test["reflection_of_type string Array(U8)"].pass =
+      "\(reflection_of_type Array(U8).new)" == "Array(U8)"
 
     test["reflection_of_runtime_type_name U64"].pass =
       (reflection_of_runtime_type_name U64[0]) == "U64"