feat: Update DropdownSelect component to display selected items based on dropdown option order

- Modified the selection display logic in the DropdownSelect component to show selected items in the order of the dropdown options, rather than the order of user selection.
- This change aims to provide a consistent and predictable user experience, reducing confusion caused by varying display orders.
- Updated the relevant documentation to reflect this new behavior and its rationale.

Made-with: Cursor

frontend/components/v2/V2Select.tsx

@@ -127,8 +127,9 @@ const DropdownSelect = forwardRef<HTMLButtonElement, {
   }, [value]);
 
   const selectedLabels = useMemo(() => {
-    return selectedValues
-      .map((v) => safeOptions.find((o) => o.value === v)?.label)
+    return safeOptions
+      .filter((o) => selectedValues.includes(o.value))
+      .map((o) => o.label)
       .filter(Boolean) as string[];
   }, [selectedValues, safeOptions]);