[IR] Dump IdSignatures and mangled names in irText tests

The reason #1 for this feature is that we want to test IdSignatures
generated for declarations. Currently, there is no (easy) way to ensure
that a change in the signature building logic doesn't cause any breaking
changes wrt klibs.

Now, most IdSignatures include hashed mangled names in them, so even if
we catch a regression where the included hash changes, there would be no
way of knowing immediately what caused it, unless we'd also have mangled
names in the expectations.

The reason #2 is to test the manglers themselves. Currently, there are
no tests for them. They heavily duplicate each other, this is already
causing issues (see KT-57427) that would be very hard to catch without
these tests.

^KT-58238 Fixed

compiler/testData/ir/irText/declarations/kt27005.sig.kt.txt

@@ -0,0 +1,21 @@
+// CHECK JVM_IR:
+//   Mangled name: #bar(){}kotlin.Any
+//   Public signature: /bar|-7451665824130722710[0]
+// CHECK JS_IR NATIVE:
+//   Mangled name: #bar(){}
+//   Public signature: /bar|496682602797471549[0]
+suspend fun bar(): Any
+
+// CHECK JVM_IR:
+//   Mangled name: #baz(){0§<kotlin.Any?>}0:0
+//   Public signature: /baz|-6572927612231176329[0]
+// CHECK JS_IR NATIVE:
+//   Mangled name: #baz(){0§<kotlin.Any?>}
+//   Public signature: /baz|-202208744392008648[0]
+suspend fun <T : Any?> baz(): T
+
+// CHECK:
+//   Mangled name: #foo(){}
+//   Public signature: /foo|-1041209573719867811[0]
+suspend fun foo(): Unit
+