perf(storage): 拦截任务二进制并本地暂存结果

原因：任务标准结果中的 Base64、Data URI 和 Buffer 会进入 PostgreSQL JSON，导致 TOAST 与备份体积快速增长。

影响：新增统一 JSON 持久化关口；upload_none 将二进制原子写入本地结果目录，数据库仅保存带 SHA-256 的有界占位符；任务详情、同步响应、异步查询和兼容协议按需校验恢复。补充 24 小时清理、容量上限、历史小批量治理命令及管理端说明。

风险：本地结果超过 TTL、丢失或损坏时分别返回明确的 410/500；空间不足时返回 503 且不重试上游。未自动执行历史治理。

验证：三种真实图片模型同步/异步与幂等重放通过；Go vet/全量测试、前端 111 测试、lint/typecheck/build、OpenAPI、迁移安全、govulncheck、依赖审计、手工发布测试及 Linux amd64 构建通过。

apps/api/internal/runner/retry_decision.go

@@ -57,6 +57,9 @@ func shouldRetrySameClient(candidate store.RuntimeModelCandidate, err error) boo
 func retryDecisionForCandidate(candidate store.RuntimeModelCandidate, err error) retryDecision {
 	policy := effectiveRetryPolicy(candidate)
 	info := failureInfoFromError(err)
+	if isResultPersistenceFailure(err) {
+		return retryDecision{Retry: false, Reason: "result_persistence_failed", Match: policyRuleMatch{Source: "gateway_result_storage", Policy: "persistence", Rule: "providerRetry", Value: "disabled"}, Info: info}
+	}
 	if errors.Is(err, store.ErrRateLimited) {
 		return retryDecision{Retry: false, Reason: "local_rate_limit_wait_queue", Match: policyRuleMatch{Source: "gateway_rate_limits", Policy: "rateLimitPolicy", Rule: "localCapacity", Value: "exceeded"}, Info: info}
 	}
@@ -77,6 +80,9 @@ func retryDecisionForCandidate(candidate store.RuntimeModelCandidate, err error)
 
 func failoverDecisionForCandidate(runnerPolicy store.RunnerPolicy, candidate store.RuntimeModelCandidate, err error) failoverDecision {
 	info := failureInfoFromError(err)
+	if isResultPersistenceFailure(err) {
+		return failoverDecision{Retry: false, Action: "stop", Reason: "result_persistence_failed", Match: policyRuleMatch{Source: "gateway_result_storage", Policy: "persistence", Rule: "providerFailover", Value: "disabled"}, Info: info}
+	}
 	if strings.TrimSpace(runnerPolicy.Status) != "" && runnerPolicy.Status != "active" {
 		return failoverDecision{Retry: false, Action: "stop", Reason: "runner_policy_disabled", Match: policyRuleMatch{Source: "gateway_runner_policies", Policy: "runnerPolicy", Rule: "status", Value: runnerPolicy.Status}, Info: info}
 	}
@@ -126,6 +132,9 @@ func shouldDemoteCandidatePriority(runnerPolicy store.RunnerPolicy, err error) b
 
 func priorityDemoteDecisionForCandidate(runnerPolicy store.RunnerPolicy, err error) priorityDemoteDecision {
 	info := failureInfoFromError(err)
+	if isResultPersistenceFailure(err) {
+		return priorityDemoteDecision{Demote: false, Reason: "result_persistence_failed", Info: info}
+	}
 	if strings.TrimSpace(runnerPolicy.Status) != "" && runnerPolicy.Status != "active" {
 		return priorityDemoteDecision{Demote: false, Reason: "runner_policy_disabled", Info: info}
 	}
@@ -145,6 +154,19 @@ func priorityDemoteDecisionForCandidate(runnerPolicy store.RunnerPolicy, err err
 	return priorityDemoteDecision{Demote: false, Reason: "priority_demote_no_match", Info: info}
 }
 
+func isResultPersistenceFailure(err error) bool {
+	switch strings.ToLower(strings.TrimSpace(clients.ErrorCode(err))) {
+	case "local_result_storage_unavailable",
+		"binary_result_too_large",
+		"binary_result_corrupted",
+		"binary_result_expired",
+		"result_binary_not_materialized":
+		return true
+	default:
+		return false
+	}
+}
+
 func effectiveFailoverPolicy(base map[string]any, override map[string]any) map[string]any {
 	policy := base
 	if nested := failoverOverridePolicy(override); len(nested) > 0 {