[FIR] Properly assign <local> packages to symbols

This prevents `FirConflictsExpressionChecker.kt`
from missing conflicting local functions. It used
to due to inconsistencies in assigning `<local>`,
and this commit makes it a bit more
straightforward.

The change in KtClassTypeQualifierRenderer
prevents `FirOverrideImplementTest.testLocalClass`
from failing in `intellij`. It didn't fail for
callables, because `KtCallableSignatureRenderer`
doesn't try to render packages.

^KT-59186 Fixed

compiler/fir/analysis-tests/testData/resolve/throwableSubclass.fir.txt

@@ -40,7 +40,7 @@ FILE: throwableSubclass.kt
 
         public final fun foo(): R|kotlin/Unit| {
             local final class Test7<Outer(T), Outer(B)> : R|kotlin/Throwable| {
-                public constructor(): R|Test5.Test7<T, B>| {
+                public constructor(): R|<local>/Test7<T, B>| {
                     super<R|kotlin/Throwable|>()
                 }
 
@@ -51,7 +51,7 @@ FILE: throwableSubclass.kt
     }
     public final fun <Z> topLevelFun(): R|kotlin/Unit| {
         local final class Test8<Outer(Z)> : R|kotlin/Error| {
-            public constructor(): R|Test8<Z>| {
+            public constructor(): R|<local>/Test8<Z>| {
                 super<R|kotlin/Error|>()
             }