feat: 完成模拟交易闭环、App 与 A 股行情接入

统一单入口 Go 工程与前端依赖目录，增加后台供应商配置、候选审核、计划预算、成交冲正、持仓复盘和站内通知。接入策略版本、Python 回测、可配置 A 股公开行情及 zap 文件轮转日志，补充迁移、契约与验证。

internal/logging/logging.go

@@ -0,0 +1,51 @@
+// Package logging supplies readable console output and rotating structured files.
+package logging
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+	"gopkg.in/natefinch/lumberjack.v2"
+)
+
+type Options struct {
+	Directory, Level                  string
+	MaxSizeMB, MaxBackups, MaxAgeDays int
+}
+
+func New(o Options) (*zap.Logger, func(), error) {
+	level, err := zapcore.ParseLevel(o.Level)
+	if err != nil {
+		return nil, nil, fmt.Errorf("invalid LOG_LEVEL")
+	}
+	if o.Directory == "" || o.MaxSizeMB < 1 || o.MaxBackups < 1 || o.MaxAgeDays < 1 {
+		return nil, nil, fmt.Errorf("invalid logging configuration")
+	}
+	if err := os.MkdirAll(o.Directory, 0750); err != nil {
+		return nil, nil, fmt.Errorf("create log directory: %w", err)
+	}
+	path := filepath.Join(o.Directory, "veyra.log")
+	f, err := os.OpenFile(path, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0600)
+	if err != nil {
+		return nil, nil, fmt.Errorf("open log file: %w", err)
+	}
+	if err := f.Close(); err != nil {
+		return nil, nil, fmt.Errorf("close initial log file: %w", err)
+	}
+	file := &lumberjack.Logger{Filename: path, MaxSize: o.MaxSizeMB, MaxBackups: o.MaxBackups, MaxAge: o.MaxAgeDays, Compress: true, LocalTime: true}
+	encoder := zap.NewProductionEncoderConfig()
+	encoder.TimeKey = "time"
+	encoder.MessageKey = "message"
+	encoder.EncodeTime = zapcore.ISO8601TimeEncoder
+	console := encoder
+	console.EncodeLevel = zapcore.CapitalLevelEncoder
+	core := zapcore.NewTee(
+		zapcore.NewCore(zapcore.NewConsoleEncoder(console), zapcore.Lock(zapcore.AddSync(os.Stdout)), level),
+		zapcore.NewCore(zapcore.NewJSONEncoder(encoder), zapcore.AddSync(file), level),
+	)
+	logger := zap.New(core, zap.AddCaller(), zap.AddStacktrace(zapcore.DPanicLevel))
+	return logger, func() { _ = logger.Sync(); _ = file.Close() }, nil
+}