feat(worker): 实现集群限流与自适应负载

保留平台模型 RPM、TPM 和并发策略语义，增加 PostgreSQL 集群级租约、饱和候选重选和多平台自动负载，避免突发任务固定等待首个平台。\n\n新增 Worker 实时负载采样、自适应 active/heavy 容量、心跳与管理端指标，并扩展本地 acceptance runner，覆盖三 Worker、同模型三平台 2/4/6 并发和 48 个带图视频突发任务。\n\n验证：go test ./...、go vet ./...、PostgreSQL 跨 Store 集成测试、gofmt、bash -n、ShellCheck 及本地集群 provider-burst 验收通过；48/48 成功，无越限、重复提交、重复计费、重复回调或终态资源泄漏。

apps/web/src/App.tsx

@@ -37,6 +37,7 @@ import type {
   UserGroupUpsertRequest,
   UserGroup,
   WalletRechargeRequest,
+  WorkerClusterRuntime,
 } from '@easyai-ai-gateway/contracts';
 import {
   batchAccessRules,
@@ -67,6 +68,7 @@ import {
   getRunnerPolicy,
   getSecurityEventConnection,
   getWalletSummary,
+  getWorkerClusterRuntime,
   listAccessRules,
   listAdminTasks,
   listAuditLogs,
@@ -201,6 +203,7 @@ type DataKey =
   | 'runtimePolicySets'
   | 'rateLimitWindows'
   | 'modelRateLimits'
+  | 'workerClusterRuntime'
   | 'tenants'
   | 'users'
   | 'userGroups'
@@ -255,6 +258,7 @@ export function App() {
   const [rateLimitWindows, setRateLimitWindows] = useState<RateLimitWindow[]>([]);
   const [modelRateLimits, setModelRateLimits] = useState<ModelRateLimitStatus[]>([]);
   const [modelRateLimitsUpdatedAt, setModelRateLimitsUpdatedAt] = useState<number | null>(null);
+  const [workerClusterRuntime, setWorkerClusterRuntime] = useState<WorkerClusterRuntime | null>(null);
   const [tenants, setTenants] = useState<GatewayTenant[]>([]);
   const [users, setUsers] = useState<GatewayUser[]>([]);
   const [userGroups, setUserGroups] = useState<UserGroup[]>([]);
@@ -381,18 +385,21 @@ export function App() {
   useEffect(() => {
     if (!token || activePage !== 'admin' || adminSection !== 'realtimeLoad') return undefined;
     const timer = window.setInterval(() => {
-      void Promise.all([listModelRateLimitStatuses(token), listPlatforms(token)])
-        .then(([rateLimitResponse, platformResponse]) => {
+      void Promise.all([listModelRateLimitStatuses(token), listPlatforms(token), getWorkerClusterRuntime(token)])
+        .then(([rateLimitResponse, platformResponse, workerRuntime]) => {
           setModelRateLimits(rateLimitResponse.items);
           setModelRateLimitsUpdatedAt(Date.now());
           setPlatforms(platformResponse.items);
+          setWorkerClusterRuntime(workerRuntime);
           loadedDataKeysRef.current.add('modelRateLimits');
           loadedDataKeysRef.current.add('platforms');
+          loadedDataKeysRef.current.add('workerClusterRuntime');
         })
         .catch((err) => {
           if (handleAuthExpired(err, token)) return;
           loadedDataKeysRef.current.delete('modelRateLimits');
           loadedDataKeysRef.current.delete('platforms');
+          loadedDataKeysRef.current.delete('workerClusterRuntime');
         });
     }, 3000);
     return () => window.clearInterval(timer);
@@ -446,6 +453,7 @@ export function App() {
     rateLimitWindows,
     modelRateLimits,
     modelRateLimitsUpdatedAt,
+    workerClusterRuntime,
     runtimePolicySets,
     securityEventConnection,
     taskResult,
@@ -455,7 +463,7 @@ export function App() {
     users,
     walletAccounts,
     walletTransactions,
-  }), [accessRules, adminTasks, apiKeys, auditLogs, baseModels, clientCustomizationSettings, currentUser, currentUserGroups, fileStorageChannels, fileStorageSettings, modelCatalog, modelRateLimits, modelRateLimitsUpdatedAt, models, networkProxyConfig, platforms, pricingRuleSets, pricingRules, providers, rateLimitWindows, runnerPolicy, runtimePolicySets, securityEventConnection, taskResult, tasks, tenants, userGroups, users, walletAccounts, walletTransactions]);
+  }), [accessRules, adminTasks, apiKeys, auditLogs, baseModels, clientCustomizationSettings, currentUser, currentUserGroups, fileStorageChannels, fileStorageSettings, modelCatalog, modelRateLimits, modelRateLimitsUpdatedAt, models, networkProxyConfig, platforms, pricingRuleSets, pricingRules, providers, rateLimitWindows, runnerPolicy, runtimePolicySets, securityEventConnection, taskResult, tasks, tenants, userGroups, users, walletAccounts, walletTransactions, workerClusterRuntime]);
 
   async function refresh(nextToken = token) {
     await ensureRouteData(nextToken, true);
@@ -593,6 +601,9 @@ export function App() {
           setModelRateLimitsUpdatedAt(Date.now());
         }
         return;
+      case 'workerClusterRuntime':
+        setWorkerClusterRuntime(await getWorkerClusterRuntime(nextToken));
+        return;
       case 'tenants':
         setTenants((await listTenants(nextToken)).items);
         return;
@@ -1255,6 +1266,7 @@ export function App() {
     setAuditLogs([]);
     setRateLimitWindows([]);
     setModelRateLimits([]);
+    setWorkerClusterRuntime(null);
     setTenants([]);
     setUsers([]);
     setUserGroups([]);
@@ -1744,7 +1756,7 @@ function dataKeysForRoute(
     case 'platforms':
       return ['platforms', 'models', 'providers', 'baseModels', 'pricingRuleSets', 'networkProxyConfig'];
     case 'realtimeLoad':
-      return ['platforms', 'modelRateLimits'];
+      return ['platforms', 'modelRateLimits', 'workerClusterRuntime'];
     case 'tasks':
       return ['adminTasks', 'tenants', 'users', 'userGroups', 'platforms', 'models'];
     case 'tenants':