[FIR] Create error candidate for completion instead of simple error reference

compiler/fir/analysis-tests/testData/resolve/callResolution/errorCandidates.kt

@@ -0,0 +1,19 @@
+fun foo(x: Int) {}
+
+interface A
+interface B
+interface C : A, B
+
+fun bar(x: A) {}
+fun bar(x: B) {}
+
+fun test(c: C) {
+    // Argument mapping error
+    <!INAPPLICABLE_CANDIDATE!>foo<!>("")
+
+    // Ambiguity
+    <!AMBIGUITY!>bar<!>(c)
+
+    // Unresolved reference
+    <!UNRESOLVED_REFERENCE!>baz<!>()
+}

compiler/fir/analysis-tests/testData/resolve/callResolution/errorCandidates.txt

@@ -0,0 +1,18 @@
+FILE: errorCandidates.kt
+    public final fun foo(x: R|kotlin/Int|): R|kotlin/Unit| {
+    }
+    public abstract interface A : R|kotlin/Any| {
+    }
+    public abstract interface B : R|kotlin/Any| {
+    }
+    public abstract interface C : R|A|, R|B| {
+    }
+    public final fun bar(x: R|A|): R|kotlin/Unit| {
+    }
+    public final fun bar(x: R|B|): R|kotlin/Unit| {
+    }
+    public final fun test(c: R|C|): R|kotlin/Unit| {
+        <Inapplicable(INAPPLICABLE): [/foo]>#(String())
+        <Ambiguity: bar, [/bar, /bar]>#(R|<local>/c|)
+        <Unresolved name: baz>#()
+    }