fix: consent banner dismiss on decline + short viewport layout

Bug 1: Clicking 'Ablehnen' now properly dismisses the dialog by calling
the delete account mutation and signing out (previously it redirected to
/settings/privacy which re-rendered the banner in a loop).

Bug 2: Restructured the dialog layout with flex-col + overflow-y-auto on
the content area only. Header and action buttons are pinned (shrink-0)
so they're always accessible on short viewports. Added max-h constraint
with min() to cap at 600px or 90vh.

cannamanage-frontend/src/components/consent-banner.tsx

@@ -3,8 +3,10 @@
 import { useState } from "react"
 import {
   useConsentCheckQuery,
+  useDeleteAccountMutation,
   useGrantConsentMutation,
 } from "@/services/consent"
+import { signOut } from "next-auth/react"
 import { useTranslations } from "next-intl"
 import { CheckCircle, Shield } from "lucide-react"
 
@@ -19,6 +21,7 @@ export function ConsentBanner() {
 
   const { data: consentCheck, isLoading } = useConsentCheckQuery()
   const grantMutation = useGrantConsentMutation()
+  const deleteMutation = useDeleteAccountMutation()
 
   // Don't show if still loading or consent already granted
   if (isLoading || consentCheck?.hasDataProcessingConsent) {
@@ -34,19 +37,25 @@ export function ConsentBanner() {
     }
   }
 
-  const handleReject = () => {
-    // Redirect to deletion confirmation
-    window.location.href = "/settings/privacy?action=delete"
+  const handleReject = async () => {
+    // Delete account and sign out — dismisses the dialog by leaving the app
+    await deleteMutation.mutateAsync()
+    await signOut({ callbackUrl: "/login" })
   }
 
+  const isPending = grantMutation.isPending || deleteMutation.isPending
+
   return (
-    <div className="fixed inset-0 z-[9999] flex items-center justify-center bg-black/70 backdrop-blur-sm">
-      <div className="mx-4 max-h-[90vh] w-full max-w-lg overflow-y-auto rounded-xl bg-card p-6 shadow-2xl">
-        <div className="mb-4 flex items-center gap-3">
+    <div className="fixed inset-0 z-[9999] flex items-center justify-center bg-black/70 backdrop-blur-sm p-4">
+      <div className="flex max-h-[min(90vh,600px)] w-full max-w-lg flex-col rounded-xl bg-card shadow-2xl">
+        {/* Header — fixed */}
+        <div className="flex shrink-0 items-center gap-3 border-b px-6 pt-6 pb-4">
           <Shield className="h-8 w-8 text-primary" />
           <h2 className="text-xl font-semibold">{t("title")}</h2>
         </div>
 
+        {/* Scrollable content */}
+        <div className="flex-1 overflow-y-auto px-6 py-4">
           {/* Required: Data Processing */}
           <div className="mb-4 rounded-lg border border-primary/20 bg-primary/5 p-4">
             <h3 className="mb-1 font-medium">{t("dataProcessing")}</h3>
@@ -59,7 +68,7 @@ export function ConsentBanner() {
           </div>
 
           {/* Optional: Marketing */}
-        <div className="mb-6 rounded-lg border p-4">
+          <div className="rounded-lg border p-4">
             <label className="flex cursor-pointer items-start gap-3">
               <input
                 type="checkbox"
@@ -75,12 +84,13 @@ export function ConsentBanner() {
               </div>
             </label>
           </div>
+        </div>
 
-        {/* Actions */}
-        <div className="flex flex-col gap-3">
+        {/* Actions — fixed at bottom */}
+        <div className="flex shrink-0 flex-col gap-3 border-t px-6 pt-4 pb-6">
           <button
             onClick={handleAccept}
-            disabled={grantMutation.isPending}
+            disabled={isPending}
             className="flex w-full items-center justify-center gap-2 rounded-lg bg-primary px-4 py-3 text-sm font-medium text-primary-foreground transition-colors hover:bg-primary/90 disabled:opacity-50"
           >
             <CheckCircle className="h-4 w-4" />
@@ -89,9 +99,10 @@ export function ConsentBanner() {
 
           <button
             onClick={handleReject}
-            className="w-full text-center text-sm text-destructive underline transition-colors hover:text-destructive/80"
+            disabled={isPending}
+            className="w-full text-center text-sm text-destructive underline transition-colors hover:text-destructive/80 disabled:opacity-50"
           >
-            {t("reject")}
+            {deleteMutation.isPending ? "..." : t("reject")}
           </button>
         </div>
       </div>