Code completion updates for enhanced switches (IDEA-202340)

- Support inside switch expression
- Support rule-based labels
- Support break inside expression
- Suggest 'switch' keyword in expressions
- Insert ':' or '->' depending on the switch type

java/java-tests/testData/codeInsight/completion/normal/LabelInRuleSwitch.java

@@ -0,0 +1,11 @@
+public class ConstConfig {
+    enum X {FOO, BAR, BAZ}
+    
+    void test(X x) {
+        switch (x) {
+            case BAR -> {}
+            case BAZ -> {}
+            case FO<caret>
+        }
+    }
+}