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/ClientForm.vue

@@ -1,4 +1,5 @@
 <script setup lang="ts">
+/* eslint-disable vue/no-mutating-props -- Inertia useForm objects are reactive and designed to be mutated via props */
 import { Building2, Plus, Settings, Trash2, User } from 'lucide-vue-next';
 import { computed } from 'vue';
 import InputError from '@/components/InputError.vue';