feat: ktlint 규칙을 위한 editorconfig 추가

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+charset=utf-8
+end_of_line=lf
+indent_style=space
+indent_size=4
+insert_final_newline=true
+disabled_rules=no-wildcard-imports,import-ordering,comment-spacing
+
+[*.{kt,kts}]
+insert_final_newline=false