[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/stubs/javaInnerClass.sig.kt.txt

@@ -0,0 +1,24 @@
+// CHECK:
+//   Mangled name: Test1
+//   Public signature: /Test1|null[0]
+class Test1 : J {
+  // CHECK:
+  //   Mangled name: Test1{}test
+  //   Public signature: /Test1.test|-5712650070209114719[0]
+  val test: JInner
+    // CHECK JVM_IR:
+    //   Mangled name: Test1#<get-test>(){}J.JInner
+    //   Public signature: /Test1.test.<get-test>|3142095303045720451[0]
+    get
+
+  // CHECK:
+  //   Mangled name: Test1#<init>(){}
+  //   Public signature: /Test1.<init>|-5645683436151566731[0]
+  constructor() /* primary */
+  // CHECK:
+  //   Mangled name: Test1#bar(){}
+  //   Public signature: /Test1.bar|496682602797471549[0]
+  /* fake */ override fun bar(): Unit
+
+}
+