Refresh Codex provider label on proxy takeover hot-switch

During proxy takeover, switching third-party Codex providers left the
client-visible provider name stale: sync_codex_live_from_provider_while_proxy_active
based the live config on the existing live file and only patched
base_url/wire_api/model, never refreshing model_provider or
model_providers.<id>.name. The Codex app kept showing the previous
provider in its bottom-right label.

Rebuild the effective settings from the DB for the selected provider so
the live config carries the correct provider key and display name, then
merge MCP servers back from the existing live config. base_url stays
pointed at the local proxy, and official OAuth in auth.json is untouched
(takeover writes config.toml only when auth preservation is enabled).

Generalize preserve_codex_mcp_servers_in_backup ->
preserve_codex_mcp_servers_from_existing_config since it now serves both
the backup and live-sync paths.

src-tauri/src/services/provider/mod.rs

@@ -1563,7 +1563,7 @@ impl ProviderService {
     /// Switch flow:
     /// 1. Validate target provider exists
     /// 2. Check if proxy takeover mode is active AND proxy server is running
-    /// 3. If takeover mode active: hot-switch proxy target only (no Live config write)
+    /// 3. If takeover mode active: hot-switch proxy target and refresh proxy-safe Live labels
     /// 4. If normal mode:
     ///    a. **Backfill mechanism**: Backfill current live config to current provider
     ///    b. Update local settings current_provider_xxx (device-level)
@@ -1631,7 +1631,9 @@ impl ProviderService {
         }
 
         if should_hot_switch {
-            // Proxy takeover mode: hot-switch only, don't write Live config
+            // Proxy takeover mode: hot-switch without restoring upstream Live config.
+            // The proxy layer may still refresh proxy-safe Live fields so client labels
+            // follow the selected provider while endpoints remain local.
             log::info!(
                 "代理接管模式：热切换 {} 的目标供应商为 {}",
                 app_type.as_str(),
@@ -1645,8 +1647,8 @@ impl ProviderService {
             )
             .map_err(|e| AppError::Message(format!("热切换失败: {e}")))?;
 
-            // Note: No Live config write, no MCP sync
-            // The proxy server will route requests to the new provider via is_current
+            // The proxy server will route requests to the new provider via is_current.
+            // MCP sync is intentionally skipped while Live config is owned by takeover.
             return Ok(SwitchResult::default());
         }
 

src-tauri/src/services/proxy.rs

@@ -322,15 +322,19 @@ impl ProxyService {
         &self,
         provider: &Provider,
     ) -> Result<(), String> {
-        let mut effective_settings = match self.read_codex_live() {
-            Ok(config) => config,
-            Err(_) => build_effective_settings_with_common_config(
-                self.db.as_ref(),
-                &AppType::Codex,
-                provider,
-            )
-            .map_err(|e| format!("构建 codex 有效配置失败: {e}"))?,
-        };
+        let existing_live = self.read_codex_live().ok();
+        let mut effective_settings = build_effective_settings_with_common_config(
+            self.db.as_ref(),
+            &AppType::Codex,
+            provider,
+        )
+        .map_err(|e| format!("构建 codex 有效配置失败: {e}"))?;
+        if let Some(existing_live) = existing_live.as_ref() {
+            Self::preserve_codex_mcp_servers_from_existing_config(
+                &mut effective_settings,
+                existing_live,
+            )?;
+        }
         let (_, proxy_codex_base_url) = self.build_proxy_urls().await?;
 
         if let Some(auth) = effective_settings
@@ -1880,7 +1884,7 @@ impl ProxyService {
                 .transpose()?;
 
             if let Some(existing_value) = existing_backup_value.as_ref() {
-                Self::preserve_codex_mcp_servers_in_backup(
+                Self::preserve_codex_mcp_servers_from_existing_config(
                     &mut effective_settings,
                     existing_value,
                 )?;
@@ -2016,9 +2020,9 @@ impl ProxyService {
         self.switch_locks.lock_for_app(app_type).await
     }
 
-    fn preserve_codex_mcp_servers_in_backup(
+    fn preserve_codex_mcp_servers_from_existing_config(
         target_settings: &mut Value,
-        existing_backup: &Value,
+        existing_config: &Value,
     ) -> Result<(), String> {
         let target_obj = target_settings
             .as_object_mut()
@@ -2036,7 +2040,7 @@ impl ProxyService {
                 .map_err(|e| format!("解析新的 Codex config.toml 失败: {e}"))?
         };
 
-        let existing_config = existing_backup
+        let existing_config = existing_config
             .get("config")
             .and_then(|v| v.as_str())
             .unwrap_or("");
@@ -2063,7 +2067,7 @@ impl ProxyService {
                         }
                     } else {
                         log::warn!(
-                            "Codex config contains a non-table mcp_servers section; skipping backup MCP merge"
+                            "Codex config contains a non-table mcp_servers section; skipping MCP merge"
                         );
                     }
                 }
@@ -2111,7 +2115,7 @@ impl ProxyService {
         Ok(())
     }
 
-    /// 代理模式下切换供应商（热切换，不写 Live）
+    /// 代理模式下切换供应商（热切换，并按需刷新代理安全的 Live 显示字段）
     pub async fn switch_proxy_target(
         &self,
         app_type: &str,
@@ -4803,6 +4807,36 @@ requires_openai_auth = true
             "provider id should point at the hot-switched provider endpoint"
         );
 
+        let live = service.read_codex_live().expect("read Codex live config");
+        let live_config = live
+            .get("config")
+            .and_then(|v| v.as_str())
+            .expect("live config string");
+        let parsed_live: toml::Value = toml::from_str(live_config).expect("parse live config");
+        assert_eq!(
+            parsed_live.get("model_provider").and_then(|v| v.as_str()),
+            Some("aihubmix"),
+            "hot-switched Codex live config should expose the selected provider"
+        );
+        assert_eq!(
+            parsed_live
+                .get("model_providers")
+                .and_then(|v| v.get("aihubmix"))
+                .and_then(|v| v.get("name"))
+                .and_then(|v| v.as_str()),
+            Some("AiHubMix"),
+            "Codex app provider label should follow the selected provider"
+        );
+        assert_eq!(
+            parsed_live
+                .get("model_providers")
+                .and_then(|v| v.get("aihubmix"))
+                .and_then(|v| v.get("base_url"))
+                .and_then(|v| v.as_str()),
+            Some("http://127.0.0.1:15721/v1"),
+            "taken-over live config should stay pointed at the local proxy"
+        );
+
         service
             .restore_live_config_for_app_with_fallback(&AppType::Codex)
             .await
@@ -4830,7 +4864,7 @@ requires_openai_auth = true
 
     #[tokio::test]
     #[serial]
-    async fn hot_switch_codex_chat_provider_uses_upstream_model_without_changing_live_provider() {
+    async fn hot_switch_codex_chat_provider_updates_live_provider_display() {
         let _home = TempHome::new();
         crate::settings::reload_settings().expect("reload settings");
 
@@ -4925,7 +4959,23 @@ requires_openai_auth = true
 
         assert_eq!(
             parsed_live.get("model_provider").and_then(|v| v.as_str()),
-            Some("stable")
+            Some("deepseek")
+        );
+        assert_eq!(
+            parsed_live
+                .get("model_providers")
+                .and_then(|v| v.get("deepseek"))
+                .and_then(|v| v.get("name"))
+                .and_then(|v| v.as_str()),
+            Some("DeepSeek")
+        );
+        assert_eq!(
+            parsed_live
+                .get("model_providers")
+                .and_then(|v| v.get("deepseek"))
+                .and_then(|v| v.get("base_url"))
+                .and_then(|v| v.as_str()),
+            Some("http://127.0.0.1:15721/v1")
         );
         assert_eq!(
             parsed_live.get("model").and_then(|v| v.as_str()),

src-tauri/tests/provider_service.rs

@@ -1302,6 +1302,11 @@ wire_api = "responses"
         live_config.contains("PROXY_MANAGED"),
         "live config should keep the proxy bearer placeholder"
     );
+    assert!(
+        live_config.contains(r#"model_provider = "deepseek-new""#)
+            && live_config.contains(r#"name = "DeepSeek New""#),
+        "live config should update the Codex-visible provider label during takeover"
+    );
     assert!(
         !live_config.contains("https://new.deepseek.example/v1"),
         "normal provider base_url must not overwrite taken-over live config"