docs: Add documentation about ListmonkButton slot

Author: roncallyt

docs/content/2.components/4.ListmonkButton.md

@@ -37,6 +37,44 @@
   ::
 ::
 
+If you want more control over button's content you can define some content like an icon or another component inside the default slot.
+
+::code-group
+  ::code-block{label="Unstyled"}
+    ```vue
+    <template>
+      <ListmonkForm>
+        <ListmonkButton>
+          <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24">
+            <path fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M4 12h16m0 0l-6-6m6 6l-6 6"/>
+          </svg>
+        </ListmonkButton>
+      </ListmonkForm>
+    </template>
+    ```
+  ::
+
+  ::code-block{label="Styled"}
+    ```vue
+    <template>
+      <ListmonkForm>
+        <ListmonkButton class="button">
+          <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24">
+            <path fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M4 12h16m0 0l-6-6m6 6l-6 6"/>
+          </svg>
+        </ListmonkButton>
+      </ListmonkForm>
+    </template>
+
+    <style scoped>
+      .button {
+         ...
+      }
+    </style>
+    ```
+  ::
+::
+
 ## Props
 
 **ListmonkButton** component has two props: