[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/contextReceivers/kt52791.sig.kt.txt

@@ -0,0 +1,20 @@
+// CHECK:
+//   Mangled name: MyClass
+//   Public signature: /MyClass|null[0]
+class MyClass {
+  // CHECK:
+  //   Mangled name computed from Ir:         MyClass#<init>(kotlin.Unit;kotlin.Int){}
+  //   Mangled name computed from Descriptor: MyClass#<init>!kotlin.Unit!kotlin.Int(){}
+  //   Public signature: /MyClass.<init>|1062323742830185042[0]
+  constructor($context_receiver_0: Unit, $context_receiver_1: Int) /* primary */
+  // CHECK:
+  //   Mangled name computed from Ir:         MyClass.contextReceiverField0
+  //   Mangled name computed from Descriptor: MyClass{}contextReceiverField0#jf
+  private /* final field */ val contextReceiverField0: Unit
+  // CHECK:
+  //   Mangled name computed from Ir:         MyClass.contextReceiverField1
+  //   Mangled name computed from Descriptor: MyClass{}contextReceiverField1#jf
+  private /* final field */ val contextReceiverField1: Int
+
+}
+