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/AppSidebar.vue

@@ -1,5 +1,5 @@
 <script setup lang="ts">
-import { Link, usePage } from '@inertiajs/vue3';
+import { usePage } from '@inertiajs/vue3';
 import {
     BookOpen,
     Briefcase,
@@ -19,16 +19,12 @@ import {
     SidebarContent,
     SidebarFooter,
     SidebarHeader,
-    SidebarMenu,
-    SidebarMenuButton,
-    SidebarMenuItem,
 } from '@/components/ui/sidebar';
 import { dashboard } from '@/routes';
 import { index as clientsIndex } from '@/routes/clients';
 import { index as declarationsIndex } from '@/routes/declarations';
 import { index as teamIndex } from '@/routes/team';
 import type { NavItem } from '@/types';
-import AppLogo from './AppLogo.vue';
 import WorkspaceSwitcher from './WorkspaceSwitcher.vue';
 
 const page = usePage();