fix(MOC-236): #477 bot review round-8(pool-miss 不退回被排除的 active provider)

round-6 pool-miss 退 default_provider()=active,但 active 本身可能未加入整合(整合时
set-default 锁定,active 可能是开整合前的遗留)→ pool-miss 仍把流量打到被排除的 active。
proxy_runner 新增 pool_default_provider_id:池化下 default = active(若在子集内)否则池首条
所属 provider(与 apply root-model 锚定一致),绝不退被排除的 active。+1 单测。

Author: Cmochance

src-tauri/src/proxy_runner.rs

@@ -261,23 +261,57 @@ fn load_resolver_snapshot() -> Result<ResolverSnapshot, String> {
         .ok_or_else(|| "gateway api key was not generated".to_owned())?;
 
     // 池化反查表:仅 `exposeAllProviderModels` 开时构建(与 catalog 生成端共用
-    // `unique_pool_slugs`,保证 slug 逐字一致)。关 → 空表 → `decide_provider` 退回
-    // slug-split / 默认 provider,行为与池化前完全一致。
-    let pool_map = if cfg.settings.expose_all_provider_models {
-        build_catalog_slug_map(&unique_pool_slugs(&cfg.providers))
+    // `unique_pool_slugs`,保证 slug 逐字一致)。关 → 空 entries → 空表 → `decide_provider`
+    // 退回 slug-split / 默认 provider,行为与池化前完全一致。
+    let pool_entries = if cfg.settings.expose_all_provider_models {
+        unique_pool_slugs(&cfg.providers)
     } else {
-        HashMap::new()
+        Vec::new()
+    };
+    let pool_map = build_catalog_slug_map(&pool_entries);
+    // 默认 provider(resolver fallback):非池化 → active。池化 → active 若在整合子集内则 active,
+    // 否则用池首条所属 provider —— **绝不**退回被排除的 active(否则 pool-miss 把流量打到用户
+    // 移出整合的 provider,#477 P2 round-8;且与 apply root-model 锚到「池首条」保持一致)。
+    let default_provider_id = if pool_entries.is_empty() {
+        cfg.active_provider.clone()
+    } else {
+        pool_default_provider_id(
+            &cfg.providers,
+            cfg.active_provider.as_deref(),
+            &pool_entries,
+        )
     };
 
     Ok(ResolverSnapshot {
         provider_count: cfg.providers.len(),
         active_provider: cfg.active_provider.clone(),
-        resolver: StaticResolver::new(Some(gateway_key), cfg.providers, cfg.active_provider)
+        resolver: StaticResolver::new(Some(gateway_key), cfg.providers, default_provider_id)
             .with_catalog_slug_map(pool_map),
         gateway_auth: true,
     })
 }
 
+/// 池化模式下 resolver 的默认 provider id。active 在整合子集(`pool_entries`)内 → 用 active;
+/// 否则退回池首条 entry 所属 provider(与 `apply` 把 root `model` 锚到池首条 slug 一致),
+/// **绝不**返回被排除的 active —— 否则 pool-miss 的请求会路由到用户移出整合的 provider
+/// (子集语义违例,#477 P2 round-8)。
+fn pool_default_provider_id(
+    providers: &[codex_app_transfer_registry::Provider],
+    active: Option<&str>,
+    pool_entries: &[codex_app_transfer_registry::PoolEntry],
+) -> Option<String> {
+    let active_idx = active.and_then(|aid| providers.iter().position(|p| p.id == aid));
+    let active_in_pool =
+        active_idx.is_some_and(|ai| pool_entries.iter().any(|e| e.provider_idx == ai));
+    if active_in_pool {
+        return active.map(str::to_owned);
+    }
+    pool_entries
+        .first()
+        .and_then(|e| providers.get(e.provider_idx))
+        .map(|p| p.id.clone())
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -289,6 +323,42 @@ mod tests {
     use crate::admin::handlers::common::test_support::with_isolated_home;
     use crate::admin::registry_io::{load as load_registry, save_for_test as save_registry};
 
+    #[test]
+    fn pool_default_provider_id_skips_excluded_active() {
+        use codex_app_transfer_registry::{PoolEntry, Provider};
+        let providers: Vec<Provider> = serde_json::from_value(json!([
+            {"id":"a","name":"A","baseUrl":"https://a","apiFormat":"openai_chat","apiKey":"k","models":{"default":"ma"}},
+            {"id":"b","name":"B","baseUrl":"https://b","apiFormat":"openai_chat","apiKey":"k","models":{"default":"mb"}},
+            {"id":"c","name":"C","baseUrl":"https://c","apiFormat":"openai_chat","apiKey":"k","models":{"default":"mc"}}
+        ]))
+        .unwrap();
+        // 整合子集 = b, c(idx 1,2);a 被排除(未加入整合)。
+        let entries = vec![
+            PoolEntry {
+                provider_idx: 1,
+                slug: "b/mb".into(),
+                real_model: "mb".into(),
+                supports_one_m: false,
+            },
+            PoolEntry {
+                provider_idx: 2,
+                slug: "c/mc".into(),
+                real_model: "mc".into(),
+                supports_one_m: false,
+            },
+        ];
+        // active=a 被排除 → 默认改用池首条所属 provider(b),绝不退回排除的 a。
+        assert_eq!(
+            pool_default_provider_id(&providers, Some("a"), &entries).as_deref(),
+            Some("b")
+        );
+        // active=b 在子集内 → 默认仍 b。
+        assert_eq!(
+            pool_default_provider_id(&providers, Some("b"), &entries).as_deref(),
+            Some("b")
+        );
+    }
+
     fn config_with_gateway(base_url: String, gateway: Value) -> Value {
         json!({
             "version": "2.1.15",