- Adopted deferred WGI_VALUE design for Result type of *_parameter and similar functions

- Adopted the ITERATION_CURSOR [WGI_VALUE] design for *_parameters and similar functions
- renamed parameter as item
- provided helper function to handle "string" value parameters

Experimental for now.

library/server/request/rest/src/contrib/doc/rest_api_documentation.e

@@ -48,7 +48,10 @@ feature -- Execution
 			rep.headers.put_content_type_text_html
 			create s.make_empty
 
-			if attached ctx.path_parameter ("resource") as l_resource then
+			if
+				attached {WGI_STRING_VALUE} ctx.path_parameter ("resource") as l_resource_value and then
+				attached l_resource_value.value as l_resource
+			then
 				from
 					hdl_cursor := router.new_cursor
 				until