FIR IDE: add HLConvertToBlockBodyIntention

idea/testData/intentions/convertToBlockBody/.firIntention

@@ -0,0 +1 @@
+org.jetbrains.kotlin.idea.fir.intentions.HLConvertToBlockBodyIntention

idea/testData/intentions/convertToBlockBody/annotatedExprInParentheses.kt

@@ -0,0 +1,5 @@
+@Target(AnnotationTarget.EXPRESSION)
+@Retention(AnnotationRetention.SOURCE)
+annotation class ann
+
+fun foo(): Int = <caret>(@ann 1)

idea/testData/intentions/convertToBlockBody/annotatedExprInParentheses.kt.after

@@ -0,0 +1,7 @@
+@Target(AnnotationTarget.EXPRESSION)
+@Retention(AnnotationRetention.SOURCE)
+annotation class ann
+
+fun foo(): Int {
+    return (@ann 1)
+}

idea/testData/intentions/convertToBlockBody/implicitlyNonUnitFun.kt.after.fir

@@ -0,0 +1,5 @@
+// WITH_RUNTIME
+
+fun foo(): String {
+    return java.io.File("x").getAbsolutePath()
+}

idea/testData/intentions/convertToBlockBody/implicitlyNonUnitFun2.kt

@@ -0,0 +1,3 @@
+// WITH_RUNTIME
+
+fun <caret>foo() = java.io.File("x").list()

idea/testData/intentions/convertToBlockBody/implicitlyNonUnitFun2.kt.after

@@ -0,0 +1,5 @@
+// WITH_RUNTIME
+
+fun foo(): Array<out String>? {
+    return java.io.File("x").list()
+}

idea/testData/intentions/convertToBlockBody/implicitlyNonUnitFun2.kt.after.fir

@@ -0,0 +1,5 @@
+// WITH_RUNTIME
+
+fun foo(): Array<out String?>? {
+    return java.io.File("x").list()
+}

idea/testData/intentions/convertToBlockBody/labeledExprInParentheses.kt

@@ -0,0 +1 @@
+fun foo(): Int = <caret>(ann@ 1)

idea/testData/intentions/convertToBlockBody/labeledExprInParentheses.kt.after

@@ -0,0 +1,3 @@
+fun foo(): Int {
+    return (ann@ 1)
+}

idea/testData/intentions/convertToBlockBody/valueIsAnonymousObject3.kt.after.fir

@@ -0,0 +1,8 @@
+interface I1
+interface I2
+
+fun f() {
+    fun g(): I1 {
+        return object : I1, I2 { }
+    }
+}