feat: Add apps sidebar tab (#9342)

## Summary

<!-- One sentence describing what changed and why. -->

## Changes

- **What**: <!-- Core functionality added/modified -->
- **Breaking**: <!-- Any breaking changes (if none, remove this line)
-->
- **Dependencies**: <!-- New dependencies (if none, remove this line)
-->

## Review Focus

<!-- Critical design decisions or edge cases that need attention -->

<!-- If this PR fixes an issue, uncomment and update the line below -->
<!-- Fixes #ISSUE_NUMBER -->

## Screenshots (if applicable)

<img width="383" height="359" alt="image"
src="https://github.com/user-attachments/assets/47905196-9db6-4a57-8cf7-384d4d37d000"
/>

<img width="335" height="281" alt="image"
src="https://github.com/user-attachments/assets/843068f3-e895-4781-bf5f-e0eb86d3387c"
/>

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9342-feat-Add-apps-sidebar-tab-3176d73d3650812b822fc9cc3f17322e)
by [Unito](https://www.unito.io)

---------

Co-authored-by: github-actions <github-actions@github.com>

src/components/common/NoResultsPlaceholder.vue

@@ -3,14 +3,18 @@
     <Card>
       <template #content>
         <div class="flex flex-col items-center">
-          <i :class="icon" style="font-size: 3rem; margin-bottom: 1rem" />
-          <h3>{{ title }}</h3>
+          <i
+            v-if="icon"
+            :class="icon"
+            style="font-size: 3rem; margin-bottom: 1rem"
+          />
+          <h3 v-if="title">{{ title }}</h3>
           <p :class="textClass" class="text-center whitespace-pre-line">
             {{ message }}
           </p>
           <Button
             v-if="buttonLabel"
-            variant="textonly"
+            :variant="buttonVariant ?? 'textonly'"
             @click="$emit('action')"
           >
             {{ buttonLabel }}
@@ -25,14 +29,16 @@
 import Card from 'primevue/card'
 
 import Button from '@/components/ui/button/Button.vue'
+import type { ButtonVariants } from '../ui/button/button.variants'
 
 const props = defineProps<{
   class?: string
   icon?: string
-  title: string
+  title?: string
   message: string
   textClass?: string
   buttonLabel?: string
+  buttonVariant?: ButtonVariants['variant']
 }>()
 
 defineEmits(['action'])
@@ -51,7 +57,6 @@ defineEmits(['action'])
 }
 
 .no-results-placeholder p {
-  color: var(--text-color-secondary);
   margin-bottom: 1rem;
 }
 </style>