Fix pricing calculator to match actual packages

Old: المبتدئ/النمو/الاحترافي/المؤسسات with wrong prices.
New: نسبة فقط (0/12%), المبتدئ (1000/7.5%), المؤسسي (3500/5%), الاحترافي (10000/3.5%).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

public/js/main.js

@@ -636,10 +636,10 @@ function initPricingCalc() {
 
   // Plan definitions: { name, monthlyFee (EGP), platformPercent }
   const plans = [
-    { id: 'starter',      name: 'المبتدئ',     monthlyFee: 500,  platformPercent: 3.0 },
-    { id: 'growth',       name: 'النمو',       monthlyFee: 1200, platformPercent: 2.0 },
-    { id: 'professional', name: 'الاحترافي',   monthlyFee: 2500, platformPercent: 1.0 },
-    { id: 'enterprise',   name: 'المؤسسات',    monthlyFee: 5000, platformPercent: 0.5 },
+    { id: 'free',         name: 'نسبة فقط',    monthlyFee: 0,     platformPercent: 12.0 },
+    { id: 'starter',      name: 'المبتدئ',     monthlyFee: 1000,  platformPercent: 7.5 },
+    { id: 'institutional',name: 'المؤسسي',     monthlyFee: 3500,  platformPercent: 5.0 },
+    { id: 'professional', name: 'الاحترافي',   monthlyFee: 10000, platformPercent: 3.5 },
   ];
 
   // Allow overriding plans via data attribute