feat(marketing): replace language input with Select; update Countries to ISO-3

- Switch language field from text `InputGroup` to `Select` with `Languages` options,
  `GlobeIcon`, clearable support, and conditional disable/require for companies
- Remove manual length validation as Select ensures valid predefined values
- Update `Countries` values from ISO-2 to ISO-3 codes for consistency

src/app/marketing/_components/MarketingForm.tsx

@@ -6,6 +6,7 @@ import { Select } from "@/components/FormElements/select";
 import { ShowcaseSection } from "@/components/Layouts/showcase-section";
 import Stepper, { Step } from "@/components/ui/Stepper";
 import { Countries } from "@/constants/countries";
+import { Languages } from "@/constants/languages";
 import { FormErrorMessages } from "@/constants/Texts";
 import { BreadcrumbItem } from "@/types/shared";
 import { useEffect, useRef, useState } from "react";
@@ -244,31 +245,24 @@ const MarketingForm = ({
               </p>
             )}
 
-            <InputGroup
-              {...registerPageType("language", {
-                required: isCompany
-                  ? { message: FormErrorMessages.required, value: true }
-                  : false,
-                minLength: isCompany
-                  ? { value: 2, message: FormErrorMessages.minLength(2) }
-                  : undefined,
-                maxLength: isCompany
-                  ? { value: 10, message: FormErrorMessages.maxLength(10) }
-                  : undefined,
-              })}
+            <Select
+              {...registerPageType("language")}
               label="Language"
               name="language"
-              type="text"
-              placeholder="Enter Language (e.g., en, ar)"
+              items={Languages}
+              defaultValue="en"
+              clearable
+              prefixIcon={<GlobeIcon />}
               disabled={!isCompany}
               required={isCompany}
+              placeholder="Please select language"
+              onClear={() => setValue("language", undefined)}
             />
             {pageTypeErrors.language && (
               <p className="mt-1 text-sm text-red-500">
                 {pageTypeErrors.language.message}
               </p>
             )}
-
             <InputGroup
               {...registerPageType("company_name", {
                 required: isCompany