🚀 refactor: migrate vendor-count aggregation to model layer & align frontend logic

Summary
• Backend
  – Moved duplicate-name validation and total vendor-count aggregation from controllers (`controller/model_meta.go`, `controller/vendor_meta.go`, `controller/prefill_group.go`) to model layer (`model/model_meta.go`, `model/vendor_meta.go`, `model/prefill_group.go`).
  – Added `GetVendorModelCounts()` and `Is*NameDuplicated()` helpers; controllers now call these instead of duplicating queries.
  – API response for `/api/models` now returns `vendor_counts` with per-vendor totals across all pages, plus `all` summary.
  – Removed redundant checks and unused imports, eliminating `go vet` warnings.

• Frontend
  – `useModelsData.js` updated to consume backend-supplied `vendor_counts`, calculate the `all` total once, and drop legacy client-side counting logic.
  – Simplified initial data flow: first render now triggers only one models request.
  – Deleted obsolete `updateVendorCounts` helper and related comments.
  – Ensured search flow also sets `vendorCounts`, keeping tab badges accurate.

Why
This refactor enforces single-responsibility (aggregation in model layer), delivers consistent totals irrespective of pagination, and removes redundant client queries, leading to cleaner code and better performance.

web/src/components/table/model-pricing/modal/components/ModelBasicInfo.jsx

@@ -71,21 +71,18 @@ const ModelBasicInfo = ({ modelData, vendorsMap = {}, t }) => {
       <div className="text-gray-600">
         <p className="mb-4">{getModelDescription()}</p>
         {getModelTags().length > 0 && (
-          <div>
-            <Text className="text-sm font-medium text-gray-700 mb-2 block">{t('模型标签')}</Text>
-            <Space wrap>
-              {getModelTags().map((tag, index) => (
-                <Tag
-                  key={index}
-                  color={tag.color}
-                  shape="circle"
-                  size="small"
-                >
-                  {tag.text}
-                </Tag>
-              ))}
-            </Space>
-          </div>
+          <Space wrap>
+            {getModelTags().map((tag, index) => (
+              <Tag
+                key={index}
+                color={tag.color}
+                shape="circle"
+                size="small"
+              >
+                {tag.text}
+              </Tag>
+            ))}
+          </Space>
         )}
       </div>
     </Card>