feat(icons): wire the universal picker into tabbar/floating settings and keep customsvg through their save paths

手机底部Tab and 右侧悬浮按钮 settings pages swap their icon text inputs
for the shared FaIconPicker (with a new IconValue preview component that
renders FA/sprite/custom SVG values in lists and previews). footer.php
tabbar/floating/sub-item icons and the VIP float render through
aksrt_icon_markup so every stored format displays; GlobalControllerPart1
and the VIP helper drop the FA-only regex gate and sanitize icon values
through aksrt_sanitize_icon_value. The picker popover tabs now wrap
instead of overflowing, and FA grid previews use style-only classes.

assets/admin/src/pages/content/FooterTabbarSettings.vue

@@ -75,7 +75,7 @@
                   <i class="fa fas fa-bars"></i>
                 </button>
                 <span class="tabbar-sort__icon">
-                  <i v-if="element.icon" :class="element.icon"></i>
+                  <IconValue v-if="element.icon" :value="element.icon" />
                 </span>
                 <div class="tabbar-sort__meta">
                   <div class="tabbar-sort__title-row">
@@ -128,16 +128,13 @@
           />
         </n-form-item>
 
-        <n-form-item label="图标 (Font Awesome)">
-          <n-input v-model:value="editingItem.icon" placeholder="例如: fa fas fa-home" />
+        <n-form-item label="图标 (Font Awesome / 内置 SVG)">
+          <FaIconPicker v-model:value="editingItem.icon" placeholder="选择图标" />
           <template #feedback>
             <div class="icon-preview-row">
               <span>预览：</span>
-              <i v-if="editingItem.icon" :class="editingItem.icon" style="font-size: 20px;"></i>
+              <IconValue v-if="editingItem.icon" :value="editingItem.icon" style="font-size: 20px;" />
               <span v-else class="muted-text">无图标</span>
-              <a href="https://fontawesome.com/search?m=free" target="_blank" rel="noopener" style="margin-left: 12px;">
-                <i class="fa fas fa-external-link-alt"></i> Font Awesome 图标库
-              </a>
             </div>
           </template>
         </n-form-item>
@@ -230,7 +227,7 @@
                     <i class="fa fas fa-bars"></i>
                   </button>
                   <n-input v-model:value="element.label" placeholder="名称，例如：写文章" />
-                  <n-input v-model:value="element.icon" placeholder="图标，例如：fa fas fa-pen" />
+                  <FaIconPicker v-model:value="element.icon" placeholder="选择图标" />
                   <n-input v-model:value="element.url" placeholder="链接，例如：/wp-admin/post-new.php" />
                   <n-button quaternary type="error" @click="removeAddItem(subIndex)">
                     <template #icon><i class="fa fas fa-trash-alt" /></template>
@@ -268,6 +265,8 @@ import { NButton, NTag, useDialog, useMessage } from 'naive-ui'
 import draggable from 'vuedraggable'
 import api from '@/api'
 import PageHeader from '@/components/PageHeader.vue'
+import FaIconPicker from '@/components/form/FaIconPicker.vue'
+import IconValue from '@/components/form/IconValue.vue'
 
 const message = useMessage()
 const dialog = useDialog()