[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/expressions/sam/samConversions.sig.kt.txt

@@ -0,0 +1,25 @@
+// CHECK:
+//   Mangled name: #test0@J(java.lang.Runnable){}
+//   Public signature: /test0|7082314898497215723[0]
+fun J.test0(a: Runnable): Unit
+
+// CHECK:
+//   Mangled name: #test1(){}
+//   Public signature: /test1|4297044443957252634[0]
+fun test1(): Unit
+
+// CHECK:
+//   Mangled name: #test2@J(){}
+//   Public signature: /test2|-509977306549568233[0]
+fun J.test2(): Unit
+
+// CHECK:
+//   Mangled name: #test3@J(kotlin.Function0<kotlin.Unit>){}
+//   Public signature: /test3|3795186268197616186[0]
+fun J.test3(a: Function0<Unit>): Unit
+
+// CHECK:
+//   Mangled name: #test4@J(kotlin.Function0<kotlin.Unit>;kotlin.Function0<kotlin.Unit>;kotlin.Boolean){}
+//   Public signature: /test4|-7934218580139307891[0]
+fun J.test4(a: Function0<Unit>, b: Function0<Unit>, flag: Boolean): Unit
+