Add a test from left over previous PR

Also: add another test that demonstrates some  behavior relating to default
parameters.

Also: Rename a test so that we don't accidentally get the test file.
In general, it's a bad idea to use a source file name in the compiler code
for a test since we often get the wrong file when loading it into the editor.

Author: odersky

tests/pos-macros/i22584/Main.scala

@@ -1,4 +1,4 @@
-import Types.*
+import types.*
 
 @main def main() =
   Macros.myMacro[MyClass1]

tests/pos-macros/i22584/Types.scala

@@ -1,4 +1,4 @@
-object Types {
+object types {
   final case class MyClass1(
     int: Int,
     string: String,

tests/run/curried-using-threading.scala

@@ -0,0 +1,10 @@
+case class Context(str: String)
+
+def root(using Context): String = summon[Context].str
+
+def narrow(using Context)(owner: String = root) = owner
+
+given Context("alpha")
+
+@main def Test = assert(narrow() == "alpha")
+