fix(linter/prefer-class-fields): insert value after type annotation in fixer (#15423)

Author: camc314

crates/oxc_linter/src/rules/unicorn/prefer_class_fields.rs

@@ -162,7 +162,9 @@ impl Rule for PreferClassFields {
                 let mut codegen = fixer.codegen();
                 codegen.print_str(" = ");
                 codegen.print_expression(&assign.right);
-                fix.push(fixer.insert_text_after(&prop.key, codegen.into_source_text()));
+                let insert_span =
+                    prop.type_annotation.as_ref().map_or(prop.key.span(), |ty| ty.span);
+                fix.push(fixer.insert_text_after_range(insert_span, codegen.into_source_text()));
             } else {
                 let indent =
                     ctx.source_range(constructor.span).lines().next().map_or("\t", |line| {
@@ -372,6 +374,11 @@ fn test() {
             "class Foo { bar = 1; constructor() {  } }",
             None,
         ),
+        (
+            "class Foo { closed: boolean; constructor() { this.closed = false; } }",
+            "class Foo { closed: boolean = false; constructor() {  } }",
+            None,
+        ),
     ];
 
     Tester::new(PreferClassFields::NAME, PreferClassFields::PLUGIN, pass, fail)