fix(app): replace Vuetify 2 legacy props with proper V3 API

Replace deprecated V2 props that were being silently ignored:
- v-layout → v-row, grid-list-md removed, xs → cols on v-col
- v-tooltip top → location="top", v-list dense → density="compact"
- v-app-bar app/scroll-off-screen → scroll-behavior="hide"
- append-outer-icon → append-icon, remove primary-title
- headline class → text-h6, remove wrap from v-row

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

app/components/pages/events/event-card.vue

@@ -1,7 +1,7 @@
 <template>
   <v-card flat variant="outlined" rounded="xl">
-    <v-card-title v-if="event.band" primary-title>
-      <h3 class="headline mb-0">
+    <v-card-title v-if="event.band">
+      <h3 class="text-h6 mb-0">
         <v-icon
           v-if="hasUser"
           class="ml-1 mr-1 text-medium-emphasis"
@@ -17,7 +17,6 @@
       <v-row dense>
         <v-col
           cols="12"
-          xs="12"
           sm="6"
         >
           <strong class="mr-1" v-text="t('events.date')" />{{
@@ -25,7 +24,7 @@
           }}
           ({{ weekday }} {{ daysUntil }})
         </v-col>
-        <v-col v-if="event.time" cols="12" xs="12" sm="6">
+        <v-col v-if="event.time" cols="12" sm="6">
           <strong class="mr-1" v-text="t('events.time')" />{{
             event.time
           }}
@@ -34,7 +33,6 @@
       <v-row v-if="event.danceHall" dense>
         <v-col
           cols="12"
-          xs="12"
           sm="6"
         >
           <strong class="mr-1" v-text="t('events.hall')" />
@@ -50,7 +48,6 @@
         </v-col>
         <v-col
           cols="12"
-          xs="12"
           sm="6"
         >
           <strong class="mr-1" v-text="t('events.city')" />
@@ -66,7 +63,6 @@
         </v-col>
         <v-col
           cols="12"
-          xs="12"
           sm="6"
         >
           <strong class="mr-1" v-text="t('events.municipality')" />
@@ -84,7 +80,6 @@
         </v-col>
         <v-col
           cols="12"
-          xs="12"
           sm="6"
         >
           <strong class="mr-1" v-text="t('events.state')" />