fix(planner): map backend role 'planner' to 'planer' and enlarge nav buttons to 40px touch targets

- hooks.server.ts: replace type-cast with actual mapping so isPlanner works
- planner page: set min-h/min-w 40px on prev/next/heute week buttons

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/hooks.server.test.ts

@@ -79,7 +79,7 @@ describe('auth guard (hooks.server.ts handle)', () => {
 					displayName: 'Max',
 					householdId: 'h1',
 					householdName: 'Familie Müller',
-					householdRole: 'planer',
+					householdRole: 'planner',
 					email: 'max@example.com',
 					systemRole: 'user'
 				}

frontend/src/hooks.server.ts

@@ -39,7 +39,7 @@ export const handle: Handle = async ({ event, resolve }) => {
 	event.locals.benutzer = {
 		id: user.id!,
 		name: user.displayName!,
-		rolle: (user.householdRole as 'planer' | 'mitglied') ?? 'mitglied'
+		rolle: user.householdRole === 'planner' ? 'planer' : 'mitglied'
 	};
 	event.locals.haushalt = {
 		id: user.householdId ?? undefined,

frontend/src/routes/(app)/planner/+page.svelte

@@ -149,7 +149,7 @@
 				type="button"
 				onclick={() => navigateWeek('prev')}
 				aria-label="Vorherige Woche"
-				class="rounded-[var(--radius-md)] border border-[var(--color-border)] p-1.5 text-[var(--color-text)] hover:bg-[var(--color-surface)]"
+				class="flex min-h-[40px] min-w-[40px] items-center justify-center rounded-[var(--radius-md)] border border-[var(--color-border)] text-[var(--color-text)] hover:bg-[var(--color-surface)]"
 			>
 				‹
 			</button>
@@ -157,7 +157,7 @@
 				type="button"
 				onclick={() => navigateWeek('next')}
 				aria-label="Nächste Woche"
-				class="rounded-[var(--radius-md)] border border-[var(--color-border)] p-1.5 text-[var(--color-text)] hover:bg-[var(--color-surface)]"
+				class="flex min-h-[40px] min-w-[40px] items-center justify-center rounded-[var(--radius-md)] border border-[var(--color-border)] text-[var(--color-text)] hover:bg-[var(--color-surface)]"
 			>
 				›
 			</button>
@@ -279,7 +279,7 @@
 				type="button"
 				onclick={() => navigateWeek('prev')}
 				aria-label="Vorherige Woche"
-				class="rounded-[var(--radius-md)] border border-[var(--color-border)] px-3 py-1.5 text-[13px] font-medium tracking-[0.04em] font-[var(--font-sans)] text-[var(--color-text)] hover:bg-[var(--color-surface)]"
+				class="flex min-h-[40px] min-w-[40px] items-center justify-center rounded-[var(--radius-md)] border border-[var(--color-border)] text-[13px] font-medium tracking-[0.04em] font-[var(--font-sans)] text-[var(--color-text)] hover:bg-[var(--color-surface)]"
 			>
 				‹
 			</button>
@@ -288,14 +288,14 @@
 				type="button"
 				onclick={() => navigateWeek('next')}
 				aria-label="Nächste Woche"
-				class="rounded-[var(--radius-md)] border border-[var(--color-border)] px-3 py-1.5 text-[13px] font-medium tracking-[0.04em] font-[var(--font-sans)] text-[var(--color-text)] hover:bg-[var(--color-surface)]"
+				class="flex min-h-[40px] min-w-[40px] items-center justify-center rounded-[var(--radius-md)] border border-[var(--color-border)] text-[13px] font-medium tracking-[0.04em] font-[var(--font-sans)] text-[var(--color-text)] hover:bg-[var(--color-surface)]"
 			>
 				›
 			</button>
 			<button
 				type="button"
 				onclick={() => navigateWeek('today')}
-				class="rounded-[var(--radius-md)] border border-[var(--color-border)] px-3 py-1.5 text-[13px] font-medium tracking-[0.04em] font-[var(--font-sans)] text-[var(--color-text)] hover:bg-[var(--color-surface)]"
+				class="flex min-h-[40px] items-center rounded-[var(--radius-md)] border border-[var(--color-border)] px-3 text-[13px] font-medium tracking-[0.04em] font-[var(--font-sans)] text-[var(--color-text)] hover:bg-[var(--color-surface)]"
 			>
 				Heute
 			</button>