feat: implement Story 2.2 — Priority Alerts Panel with UI fixes

Add PriorityAlertsPanel component to the dashboard, update DashboardController
with alert logic, and apply misc UI fixes across sidebar, forms, and pages.
Includes epic-1 retrospective and sprint status update.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

resources/js/components/WorkspaceSwitcher.vue

@@ -1,7 +1,7 @@
 <script setup lang="ts">
-import { computed, ref } from 'vue';
 import { router, usePage } from '@inertiajs/vue3';
 import { BoxSelect, Check, ChevronsUpDown } from 'lucide-vue-next';
+import { computed, ref } from 'vue';
 import {
     DropdownMenu,
     DropdownMenuContent,