refactor: organize compatibility features design docs into subdirectory

Author: yuanyl630

CN/modules/ROOT/nav.adoc

@@ -44,18 +44,18 @@
 **** xref:master/dual_mode_design.adoc[双模式设计]
 **** xref:master/initdb_process.adoc[initdb过程]
 *** 兼容特性
-**** xref:master/like_operator.adoc[like]
-**** xref:master/rowid.adoc[RowID]
-**** xref:master/out_parameter.adoc[OUT 参数]
-**** xref:master/type_rowtype.adoc[%TYPE、%ROWTYPE]
-**** xref:master/nls_parameter.adoc[NLS 参数]
-**** xref:master/function_procedure.adoc[函数与存储过程]
-**** xref:master/nested_function.adoc[嵌套子函数]
-**** xref:master/force_view.adoc[Force View]
-**** xref:master/case_conversion.adoc[大小写转换]
-**** xref:master/sys_guid_function.adoc[sys_guid 函数]
-**** xref:master/empty_string_to_null.adoc[空字符串转null]
-**** xref:master/call_into.adoc[CALL INTO]
+**** xref:master/compatibility_features_design/like_operator.adoc[like]
+**** xref:master/compatibility_features_design/rowid.adoc[RowID]
+**** xref:master/compatibility_features_design/out_parameter.adoc[OUT 参数]
+**** xref:master/compatibility_features_design/type_rowtype.adoc[%TYPE、%ROWTYPE]
+**** xref:master/compatibility_features_design/nls_parameter.adoc[NLS 参数]
+**** xref:master/compatibility_features_design/function_procedure.adoc[函数与存储过程]
+**** xref:master/compatibility_features_design/nested_function.adoc[嵌套子函数]
+**** xref:master/compatibility_features_design/force_view.adoc[Force View]
+**** xref:master/compatibility_features_design/case_conversion.adoc[大小写转换]
+**** xref:master/compatibility_features_design/sys_guid_function.adoc[sys_guid 函数]
+**** xref:master/compatibility_features_design/empty_string_to_null.adoc[空字符串转null]
+**** xref:master/compatibility_features_design/call_into.adoc[CALL INTO]
 *** 内置函数
 **** xref:master/sys_context.adoc[sys_context]
 **** xref:master/userenv.adoc[userenv]