feat: optimize logo display (#6267)

* feat(VbenAvatar): add fit property to VbenAvatar component

* feat(VbenLogo): add fit property to VbenLogo component

* feat(VbenLogo): add logo fit preference configuration

- Add preferences.logo.fit setting for logo display control
- Include corresponding documentation for the new preference

* feat(preferences): add default value for logo.fit preference

- Set default configuration for logo fit behavior
- Ensures consistent logo display across applications

* test(preferences): update configuration snapshots

---------

Co-authored-by: wyc001122 <wangyongchao@testor.com.cn>

packages/effects/layouts/src/basic/layout.vue

@@ -234,6 +234,7 @@ const headerSlots = computed(() => {
     <template #logo>
       <VbenLogo
         v-if="preferences.logo.enable"
+        :fit="preferences.logo.fit"
         :class="logoClass"
         :collapsed="logoCollapsed"
         :src="preferences.logo.source"
@@ -324,6 +325,7 @@ const headerSlots = computed(() => {
     <template #side-extra-title>
       <VbenLogo
         v-if="preferences.logo.enable"
+        :fit="preferences.logo.fit"
         :text="preferences.app.name"
         :theme="theme"
       >