feat: Unify the 'Add Model Provider' modal (#15768)

### What problem does this PR solve?

feat：Unify the 'Add Model Provider' modal

### Type of change

- [x] New Feature (non-breaking change which adds functionality)
- [x] Refactoring

web/src/interfaces/database/llm.ts

@@ -54,6 +54,12 @@ export interface IProviderInstance {
   provider_id: string;
   region: string;
   status: string;
+  /**
+   * Optional: only returned by the showProviderInstance endpoint. Used
+   * to pre-fill the base_url/api_base form field in the ProviderModal
+   * (e.g. when opening an existing instance in viewMode).
+   */
+  base_url?: string;
 }
 export interface IAddedModel {
   model_type: string[];

web/src/interfaces/request/llm.ts

@@ -1,12 +1,25 @@
 export interface IAddLlmRequestBody {
   llm_factory: string; // Ollama
-  llm_name: string;
-  model_type: string | string[];
-  api_base?: string; // chat|embedding|speech2text|image2text
+  // model_name: string;
+  // model_type: string | string[];
+  base_url?: string; // chat|embedding|speech2text|image2text
   api_key?: string | Record<string, any>;
   max_tokens: number;
   is_tools?: boolean;
   region?: string;
+  model_info: IModelInfo[];
+}
+
+export interface IModelInfo {
+  model_name: string;
+  model_type: string | string[];
+  max_tokens: number;
+  /**
+   * Per-model extras (e.g. `is_tools` derived from the model descriptor's
+   * `features`). Optional for backward compatibility with legacy
+   * single-model payloads.
+   */
+  extra?: Record<string, any>;
 }
 
 export interface IDeleteLlmRequestBody {
@@ -61,3 +74,27 @@ export interface ISetDefaultModelRequestBody {
   model_type: string;
   model_name: string;
 }
+
+/**
+ * Item shape returned by the list-provider-models endpoint.
+ * Fields match the backend's available-model descriptor.
+ */
+export interface IProviderModelItem {
+  name: string;
+  max_tokens: number;
+  model_types: string[];
+  features: string[] | null;
+}
+
+/**
+ * Request payload for the list-provider-models endpoint.
+ * Mirrors the verifyProviderConnection payload so the same form
+ * fields (api_key, base_url, region, model_info) can be reused.
+ */
+export interface IListProviderModelsRequestBody {
+  provider_name: string;
+  api_key: string;
+  base_url?: string;
+  region?: string;
+  model_info?: IModelInfo[];
+}