feat(primevue): add Icon component and mount Toast + ConfirmDialog services

Two additions complete the F3 runtime scaffolding:

apps/app/src/components/Icon.vue — generic Iconify renderer wrapping
@iconify/vue's <Icon> component. F4 migration substitutes
<VIcon icon="tabler-X" /> with <Icon name="tabler-X" /> at call-sites,
producing real SVG output and using the existing Crewli "tabler-*"
naming convention. Props: name (required, e.g. "tabler-eye"), optional
size. The component avoids @iconify/vue's auto-import for clarity at
call-sites.

apps/app/src/App.vue — mounts <Toast /> and <ConfirmDialog /> at the
template root inside VLocaleProvider. Both render alongside the
existing VSnackbar and VDialog confirm patterns during the F3–F4
parallel-mode window. F4 sub-packages migrate call-sites to PrimeVue's
useToast() / useConfirm() composables.

UnoCSS-style i-tabler-* utility-class rendering (RFC AD-5 v1.0 wording)
is not adopted — UnoCSS is not installed in the Crewli stack. The
RFC will be aligned in B9.

Verification:
- pnpm typecheck — clean.
- pnpm test — 402 tests pass unchanged.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/app/src/App.vue

@@ -1,5 +1,7 @@
 <script setup lang="ts">
 import { useTheme } from 'vuetify'
+import Toast from 'primevue/toast'
+import ConfirmDialog from 'primevue/confirmdialog'
 import ScrollToTop from '@core/components/ScrollToTop.vue'
 import initCore from '@core/initCore'
 import { initConfigStore, useConfigStore } from '@core/stores/config'
@@ -68,5 +70,13 @@ authStore.initialize()
         </VBtn>
       </template>
     </VSnackbar>
+
+    <!--
+      PrimeVue overlay services (F3 — parallel-mode with VSnackbar above
+      and the legacy VDialog confirm patterns until F4 sub-packages
+      migrate call-sites to useToast() and useConfirm()).
+    -->
+    <Toast />
+    <ConfirmDialog />
   </VLocaleProvider>
 </template>