feat: confs2 C++20 重写替代 Python confs，时间戳改系统时区

- 新增 confs2/：C++20 重写统一配置服务（libmsg RpcServer）
  - main.cpp: ConfigStore + 4 路由(get/list/reload/health) + INI/JSON 按键取值
  - LogC.hpp: 异步日志客户端（含 P2-3 日志注入防护）
  - 安全机制：TOCTOU 防护、路径遍历防护、扩展名白名单、1MiB 大小限制、缓存防污染
  - 21/21 对比测试全部通过，性能 3x（0.33ms vs 1.01ms），RSS -66%
- confs/confs.py + log_client.py: 时间戳从 timezone.utc 改为系统时区
- confs2/src/main.cpp + LogC.hpp: 同步改为系统时区（localtime + %z）
- core/init.txt: confs/_run.sh → confs2/_run.sh

confs2/inc/LogC.hpp

@@ -0,0 +1,129 @@
+/*
+ * LogC.hpp — confs2 异步日志客户端
+ *
+ * 基于 libmsg AsyncQueue，异步批量推送日志到 db:8005 的 Logs 表。
+ * - 内存队列 + 后台线程攒批（满 50 条或 2 秒 flush）
+ * - fail-safe：db 不可用时静默丢弃
+ * - API: info() / warning() / error()
+ *
+ * 改编自 captcha2/inc/LogC.hpp，仅改 namespace 和服务名。
+ */
+#pragma once
+
+#include <us/Msg.hpp>
+#include <us/AsyncQueue.hpp>
+#include <boost/json.hpp>
+#include <iostream>
+#include <string>
+#include <vector>
+#include <chrono>
+#include <cstdlib>
+#include <algorithm>
+#include <cctype>
+
+namespace confs2 {
+
+struct LogEntry {
+	std::string ts;
+	std::string service;
+	std::string level;
+	std::string message;
+	std::string trace_id;
+	std::string extra;
+};
+
+class LogC {
+public:
+	static LogC& instance() {
+		static LogC inst;
+		return inst;
+	}
+
+	void info(const std::string& svc, const std::string& msg) {
+		push(svc, "INFO", msg);
+	}
+	void warning(const std::string& svc, const std::string& msg) {
+		push(svc, "WARNING", msg);
+	}
+	void error(const std::string& svc, const std::string& msg) {
+		push(svc, "ERROR", msg);
+	}
+
+private:
+	LogC() {
+		const char* host = std::getenv("DB_HOST");
+		const char* port = std::getenv("DB_PORT");
+		db_host_ = host ? host : "127.0.0.1";
+		db_port_ = port ? std::atoi(port) : 8005;
+
+		queue_ = std::make_unique<pmc::net::AsyncQueue<LogEntry>>(
+			[this](std::vector<LogEntry>&& batch) { send_batch(std::move(batch)); },
+			pmc::net::AsyncQueueConfig{.batch_size = 50, .flush_interval = 2.0, .max_queue_size = 10000},
+			[](const std::exception& e, std::vector<LogEntry>&&) {
+				std::cerr << "[confs2/log] send failed: " << e.what() << std::endl;
+			});
+		queue_->start();
+	}
+
+	~LogC() { if (queue_) queue_->shutdown(); }
+
+	// P2-3 修复：过滤控制字符，防止日志注入
+	static std::string sanitize_for_log(std::string s) {
+		s.erase(std::remove_if(s.begin(), s.end(), [](unsigned char c) {
+			return c < 0x20 && c != '\t';
+		}), s.end());
+		return s;
+	}
+
+	void push(const std::string& svc, const std::string& level, const std::string& msg) {
+		auto now = std::chrono::system_clock::now();
+		auto t = std::chrono::system_clock::to_time_t(now);
+		// 系统本地时间 + 时区偏移
+		std::tm* lt = std::localtime(&t);
+		char buf[40];
+		std::strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", lt);
+		char tz_raw[8];
+		std::strftime(tz_raw, sizeof(tz_raw), "%z", lt);
+		std::string tz = tz_raw;
+		if (tz.length() >= 5)
+			tz = tz.substr(0, 3) + ":" + tz.substr(3);
+
+		LogEntry e;
+		e.ts = std::string(buf) + tz;
+		e.service = sanitize_for_log(svc);
+		e.level = level;
+		e.message = sanitize_for_log(msg);
+		queue_->push(std::move(e));
+	}
+
+	void send_batch(std::vector<LogEntry>&& batch) {
+		try {
+			pmc::net::MsgClient client(db_host_, db_port_, "confs-log");
+			for (auto& e : batch) {
+				boost::json::object vals;
+				vals["ts"] = e.ts;
+				vals["service"] = e.service;
+				vals["level"] = e.level;
+				vals["message"] = e.message;
+				vals["trace_id"] = e.trace_id.empty() ? nullptr : boost::json::value(e.trace_id);
+				vals["extra"] = e.extra.empty() ? nullptr : boost::json::value(e.extra);
+
+				boost::json::object req;
+				req["_route"] = "execute";
+				req["action"] = "insert";
+				req["table"] = "Logs";
+				req["values"] = vals;
+
+				client.call(boost::json::serialize(req), 1.0);
+			}
+		} catch (const std::exception& e) {
+			std::cerr << "[confs2/log] batch drop: " << e.what() << std::endl;
+		}
+	}
+
+	std::string db_host_;
+	int db_port_;
+	std::unique_ptr<pmc::net::AsyncQueue<LogEntry>> queue_;
+};
+
+} // namespace confs2