feat(grokbuild): add first-class Grok Build support (#5453)

* feat(grokbuild): add backend integration

* feat(grokbuild): add provider and management UI

* test(grokbuild): cover configuration and integrations

* fix(grokbuild): address backend review feedback

* fix(grokbuild): complete UI review feedback

* feat(grokbuild): add CLI lifecycle management

* fix(grokbuild): align provider icon fallback

* test(grokbuild): cover provider icon persistence

src-tauri/src/proxy/server.rs

@@ -327,6 +327,12 @@ impl ProxyServer {
             .route("/v1/responses", post(handlers::handle_responses))
             .route("/v1/v1/responses", post(handlers::handle_responses))
             .route("/codex/v1/responses", post(handlers::handle_responses))
+            // Grok Build uses the Responses protocol but has an independent
+            // provider namespace and failover queue.
+            .route(
+                "/grokbuild/v1/responses",
+                post(handlers::handle_grokbuild_responses),
+            )
             // OpenAI Responses Compact API (Codex CLI 远程压缩，透传)
             .route(
                 "/responses/compact",
@@ -344,6 +350,10 @@ impl ProxyServer {
                 "/codex/v1/responses/compact",
                 post(handlers::handle_responses_compact),
             )
+            .route(
+                "/grokbuild/v1/responses/compact",
+                post(handlers::handle_grokbuild_responses_compact),
+            )
             // Gemini API (支持带前缀和不带前缀)
             //
             // 用 `any(..)` 覆盖所有 HTTP 方法：除了 POST `:generateContent` /