[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/breakContinueInLoopHeader.sig.kt.txt

@@ -0,0 +1,25 @@
+// CHECK:
+//   Mangled name: #test1(kotlin.Boolean?){}
+//   Public signature: /test1|-614655814357645647[0]
+fun test1(c: Boolean?): Unit
+
+// CHECK:
+//   Mangled name: #test2(kotlin.Boolean?){}
+//   Public signature: /test2|433529625541321478[0]
+fun test2(c: Boolean?): Unit
+
+// CHECK:
+//   Mangled name: #test3(kotlin.collections.List<kotlin.String>?){}
+//   Public signature: /test3|7517805814041019716[0]
+fun test3(ss: List<String>?): Unit
+
+// CHECK:
+//   Mangled name: #test4(kotlin.collections.List<kotlin.String>?){}
+//   Public signature: /test4|1371726193385654339[0]
+fun test4(ss: List<String>?): Unit
+
+// CHECK:
+//   Mangled name: #test5(){}
+//   Public signature: /test5|-2461239215881954159[0]
+fun test5(): Unit
+