feat: 新增 frontdoor 执行回环守卫与多项可观测性增强

- 新增 frontdoor_loop_guard 模块，检测并拒绝 execution runtime 回环到本地网关的请求（HTTP 508）
- candidate loop 引入 span tracking、执行尝试日志与流式看门狗超时
- 本地故障转移策略支持从 report_context 加载，新增 append_local_failover_policy_to_value
- runtime tracing 美化：移除 identity 前缀，按 span 深度树形缩进，target 固定宽度展示
- Codex OpenAI CLI 补齐 chatgpt-account-id/x-client-request-id/session_id/conversation_id 请求头
- OpenAI CLI same/cross-format 聚合规则放宽以支持 openai:compact 客户端格式，并过滤 error-like 响应体
- auth/proxy/finalize 日志补充 user_id/api_key_id/api_key_name/balance_remaining 等字段
- 启动日志拆分为 starting/ready/config 三段，新增 resolve_bind_http_base_url
- access_log middleware 将生成的 trace_id 回注到下游请求头
- Cargo.toml 启用 serde_json preserve_order 特性

apps/aether-gateway/src/control/auth/resolution.rs

@@ -151,6 +151,10 @@ fn log_auth_context_resolution(
     decision: &GatewayControlDecision,
     auth_context: &GatewayControlAuthContext,
 ) {
+    let balance_remaining = auth_context
+        .balance_remaining
+        .map(|value| format!("{value:.4}"))
+        .unwrap_or_else(|| "-".to_string());
     info!(
         event_name = "auth_context_resolved",
         log_type = "event",
@@ -165,6 +169,8 @@ fn log_auth_context_resolution(
         route_kind = decision.route_kind.as_deref().unwrap_or("unknown"),
         user_id = auth_context.user_id.as_str(),
         api_key_id = auth_context.api_key_id.as_str(),
+        api_key_name = auth_context.api_key_name.as_deref().unwrap_or("-"),
+        balance_remaining = balance_remaining.as_str(),
         access_allowed = auth_context.access_allowed,
         api_key_is_standalone = auth_context.api_key_is_standalone,
         has_local_rejection = auth_context.local_rejection.is_some(),