Add two new themes: Red & Brown (#1721)

## Description
Adds new two new theme colors: Red & Brown

### Related issues
Related to #91, #950
Closes #1646

### Testing
<!-- Describe how this change was tested and on what device(s) -->

## Screenshots
<img width="2727" height="2171" alt="image"
src="https://github.com/user-attachments/assets/ae19f98d-e782-466a-bafc-6c0502f64e00"
/>

## AI or LLM usage
None

app/src/main/res/values/strings.xml

@@ -599,6 +599,7 @@
     <string name="orange">Orange</string>
     <string name="bold_blue">Bold Blue</string>
     <string name="black">Black</string>
+    <string name="brown">Brown</string>
     <string-array name="app_theme_colors">
         <item>@string/purple</item>
         <item>@string/blue</item>
@@ -606,6 +607,8 @@
         <item>@string/orange</item>
         <item>@string/bold_blue</item>
         <item>@string/black</item>
+        <item>@string/red</item>
+        <item>@string/brown</item>
     </string-array>
 
     <string name="skip_ignore">Ignore</string>