fix(cache): 存量空/url 策略规范为 all，避免静默收窄

评审修复：enabled 且 policy 为空或 url 时，写入/展示/快照/渲染均映射为 all，
保证旧站点宽缓存范围不变；新建 UI 仍显式提交 static 作为推荐默认。

frontend/app/(main)/proxy-routes/components/helpers.ts

@@ -335,12 +335,17 @@ export function buildPayloadFromRoute(
     limit_conn_per_ip: route.limit_conn_per_ip,
     limit_rate: route.limit_rate,
     cache_enabled: route.cache_enabled,
-    cache_policy:
-      !route.cache_policy || route.cache_policy === 'url'
-        ? route.cache_policy === 'url'
-          ? 'all'
-          : 'static'
-        : route.cache_policy,
+    cache_policy: (() => {
+      if (!route.cache_enabled) {
+        return 'static';
+      }
+      const policy = (route.cache_policy || '').trim();
+      // Legacy empty/url → all (same as backend displayCachePolicy).
+      if (!policy || policy === 'url' || policy === 'all') {
+        return 'all';
+      }
+      return policy;
+    })(),
     cache_rules: route.cache_rule_list ?? [],
     custom_headers: route.custom_header_list ?? [],
     basic_auth_enabled: route.basic_auth_enabled,

frontend/app/(main)/proxy-routes/detail/components/cache-section.tsx

@@ -39,7 +39,6 @@ const cacheSchema = z
     cache_policy: z.enum([
       'static',
       'all',
-      'url',
       'suffix',
       'path_prefix',
       'path_exact',
@@ -70,10 +69,17 @@ interface CacheSectionProps {
   onSavingChange?: (saving: boolean) => void;
 }
 
-function normalizeCachePolicyValue(policy: string | undefined | null) {
+/** Map API/DB values for the form. Legacy empty/url → all (compat). */
+function normalizeCachePolicyValue(
+  policy: string | undefined | null,
+  enabled = true,
+) {
+  if (!enabled) {
+    return 'static';
+  }
   const value = (policy || '').trim();
-  if (!value || value === 'static') return 'static';
-  if (value === 'url' || value === 'all') return 'all';
+  if (!value || value === 'url' || value === 'all') return 'all';
+  if (value === 'static') return 'static';
   if (value === 'suffix' || value === 'path_prefix' || value === 'path_exact') {
     return value;
   }
@@ -103,6 +109,7 @@ export function CacheSection({
       cache_enabled: route.cache_enabled,
       cache_policy: normalizeCachePolicyValue(
         route.cache_policy,
+        route.cache_enabled,
       ) as CacheValues['cache_policy'],
       cache_rules_text: route.cache_rule_list.join('\n'),
     },
@@ -113,6 +120,7 @@ export function CacheSection({
       cache_enabled: route.cache_enabled,
       cache_policy: normalizeCachePolicyValue(
         route.cache_policy,
+        route.cache_enabled,
       ) as CacheValues['cache_policy'],
       cache_rules_text: route.cache_rule_list.join('\n'),
     });
@@ -161,9 +169,7 @@ export function CacheSection({
             await save(
               {
                 cache_enabled: values.cache_enabled,
-                cache_policy: values.cache_enabled
-                  ? normalizeCachePolicyValue(values.cache_policy)
-                  : 'static',
+                cache_policy: values.cache_enabled ? values.cache_policy : '',
                 cache_rules:
                   values.cache_enabled &&
                   needsRulesForPolicy(values.cache_policy)
@@ -182,8 +188,9 @@ export function CacheSection({
                 <div className='space-y-0.5'>
                   <FormLabel>启用站点缓存</FormLabel>
                   <FormDescription>
-                    开启后默认仅缓存标准静态扩展名（不含 HTML）。仍会自动绕过非
-                    GET、Authorization 与常见登录态 Cookie。
+                    新建推荐「标准静态资源」（不含
+                    HTML）。须同时开启性能设置中的全局 OpenResty
+                    缓存。仍会绕过非 GET、Authorization 与常见登录 Cookie。
                   </FormDescription>
                 </div>
                 <FormControl>