Referral page, bug fixes, seed data, persona tiers

- New /refer page with share/copy/stats
- Fixed modal z-index conflicts (z-50 → z-[60]) across forum, groups, souq, halal-monitor
- Seed route: forum categories, marketplace listings, private groups
- Mufti/Daie personas now available in Premium tier
- Fixed referral share link: falahos.my/mobile/auth?ref=CODE
- Fixed client-side persona access check for premium

src/app/api/referrals/stats/route.ts

@@ -1,24 +1,7 @@
 import { NextRequest, NextResponse } from "next/server";
 import { prisma } from "@/lib/prisma";
 import { requireAuth } from "@/lib/auth";
-
-// Same encodeBase62 used in the code route
-function encodeBase62(id: string): string {
-  const chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
-  let hash = 0;
-  for (let i = 0; i < Math.min(id.length, 10); i++) {
-    hash = (hash * 31 + id.charCodeAt(i)) >>> 0;
-  }
-  let code = "";
-  while (code.length < 6) {
-    code = chars[hash % 62] + code;
-    hash = Math.floor(hash / 62);
-    if (hash === 0 && code.length < 6) {
-      hash = Math.floor(Math.random() * 62 ** (6 - code.length));
-    }
-  }
-  return code;
-}
+import { encodeReferralCode } from "@/lib/referral";
 
 export async function GET(req: NextRequest) {
   const jwtPayload = await requireAuth(req);
@@ -42,14 +25,14 @@ export async function GET(req: NextRequest) {
       }),
     ]);
 
-    const referralCode = encodeBase62(userId);
+    const referralCode = encodeReferralCode(userId);
 
     return NextResponse.json({
       totalReferrals,
       upgradedCount,
       totalEarned: earnings._sum.rewardFlh || 0,
       referralCode,
-      shareLink: `${process.env.NEXT_PUBLIC_APP_URL || "https://falah.app"}/join?ref=${referralCode}`,
+      shareLink: `${process.env.NEXT_PUBLIC_APP_URL || "https://falahos.my/mobile"}/auth?ref=${referralCode}`,
     });
   } catch (error) {
     console.error("Referral stats error:", error);