[java-import] IDEA-369199 Preserve module imports even if they are not used

- new options
- don't highlight such imports as unused
- delete imports of nested modules
- preserve high-level modules during 'optimize import'

GitOrigin-RevId: 3728f41a934f320767caac0a643a5869ccc84bcc

java/java-tests/testData/codeStyle/notFirstImportModule.json

@@ -69,6 +69,7 @@
       "class_names_in_javadoc": 1,
       "continuation_indent_size": 8,
       "deconstruction_list_wrap": "normal",
+      "delete_unused_module_imports": false,
       "do_not_indent_top_level_class_members": false,
       "do_not_wrap_after_single_annotation": false,
       "do_not_wrap_after_single_annotation_in_parameter": false,