fix(api): nvim_create_user_command addr option should allow ranges #35077

Problem: Using `addr` without `range` in nvim_create_user_command gives
"No range allowed" error, inconsistent with `:command -addr` behavior.

Solution: Set EX_RANGE flag when `addr` option is specified to match
`:command` behavior.

src/nvim/api/command.c

@@ -1170,6 +1170,7 @@ void create_user_command(uint64_t channel_id, String name, Union(String, LuaRef)
       goto err;
     });
 
+    argt |= EX_RANGE;
     if (addr_type_arg != ADDR_LINES) {
       argt |= EX_ZEROR;
     }