fix(upload-model): UI/UX improvements for Upload Model Dialog (#7969)

## Summary

Addresses UI/UX feedback on the Upload Model Dialog (BYOM feature).

## Changes

1. **Standardize link styling** - Use consistent `text-muted-foreground
underline` for all links in both URL input variants
2. **Increase warning/example text font size** - Changed from 12px
(`text-xs`) to 14px (`text-sm`) for better readability
3. **Fix padding inconsistency** - Aligned padding between model name
box and SingleSelect dropdown; moved "Not sure?" help text inline with
the label
4. **Add "Upload Another" button** - Allows users to upload multiple
models without closing and reopening the dialog

## Testing

- Verified link styling consistency across both Civitai and generic URL
input components
- Confirmed padding alignment in confirmation step
- Tested Upload Another button resets wizard to step 1

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7969-fix-upload-model-UI-UX-improvements-for-Upload-Model-Dialog-2e66d73d3650815c8184cedb3d02672d)
by [Unito](https://www.unito.io)

src/platform/assets/components/UploadModelFooter.vue

@@ -80,21 +80,33 @@
       <i v-if="isUploading" class="icon-[lucide--loader-circle] animate-spin" />
       <span>{{ $t('assetBrowser.upload') }}</span>
     </Button>
-    <Button
+    <template
       v-else-if="
         currentStep === 3 &&
         (uploadStatus === 'success' || uploadStatus === 'processing')
       "
-      variant="secondary"
-      data-attr="upload-model-step3-finish-button"
-      @click="emit('close')"
     >
-      {{
-        uploadStatus === 'processing'
-          ? $t('g.close')
-          : $t('assetBrowser.finish')
-      }}
-    </Button>
+      <Button
+        variant="muted-textonly"
+        size="lg"
+        data-attr="upload-model-step3-import-another-button"
+        @click="emit('importAnother')"
+      >
+        {{ $t('assetBrowser.importAnother') }}
+      </Button>
+      <Button
+        variant="secondary"
+        size="lg"
+        data-attr="upload-model-step3-finish-button"
+        @click="emit('close')"
+      >
+        {{
+          uploadStatus === 'processing'
+            ? $t('g.close')
+            : $t('assetBrowser.finish')
+        }}
+      </Button>
+    </template>
     <VideoHelpDialog
       v-model="showCivitaiHelp"
       video-url="https://media.comfy.org/compressed_768/civitai_howto.webm"
@@ -134,5 +146,6 @@ const emit = defineEmits<{
   (e: 'fetchMetadata'): void
   (e: 'upload'): void
   (e: 'close'): void
+  (e: 'importAnother'): void
 }>()
 </script>