feat: M0-M2 骨架落地（服务端/前端/宿主/数据库/积分引擎）

- server: Go 单二进制骨架，embed 内嵌前端，配置/迁移/HTTP 路由
- store: system.db + event.db 两套迁移，业务表 + 种子数据
- domain: 积分引擎（并列三口径/计分通道/流水/排名/破纪录）+ 68 个测试
- web: Vite + Vue 三入口骨架 + shared 层（类型/API/WebSocket 客户端）
- console: Electron 宿主骨架（选屏/防熄屏/进程守护/托盘）

server/internal/httpapi/router.go

@@ -0,0 +1,107 @@
+// Package httpapi 提供 HTTP 接口与静态资源托管。
+package httpapi
+
+import (
+	"encoding/json"
+	"io/fs"
+	"log/slog"
+	"net/http"
+	"strings"
+	"time"
+
+	"git.yeij.top/AskaEth/Scoreboard/server/internal/webui"
+)
+
+// Options 是构建路由所需的依赖。
+type Options struct {
+	Logger  *slog.Logger
+	Version string
+}
+
+// New 组装并返回服务端的 HTTP 处理器。
+func New(opts Options) http.Handler {
+	logger := opts.Logger
+	if logger == nil {
+		logger = slog.Default()
+	}
+
+	mux := http.NewServeMux()
+
+	mux.HandleFunc("GET /api/health", func(w http.ResponseWriter, r *http.Request) {
+		writeJSON(w, http.StatusOK, map[string]any{
+			"ok":      true,
+			"version": opts.Version,
+		})
+	})
+
+	assets, err := webui.FS()
+	if err != nil {
+		logger.Error("前端资源不可用", "err", err)
+		mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+			http.Error(w, "前端资源不可用", http.StatusServiceUnavailable)
+		})
+	} else {
+		mux.Handle("/", staticHandler(assets))
+	}
+
+	return withRequestLog(mux, logger)
+}
+
+// staticHandler 把 URL 映射到多页面前端产物。
+//
+//	/            → index.html
+//	/display     → display.html
+//	/admin       → admin.html
+//	/其他         → 按文件路径查找
+func staticHandler(assets fs.FS) http.Handler {
+	files := http.FileServerFS(assets)
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		p := strings.TrimPrefix(r.URL.Path, "/")
+
+		switch p {
+		case "", "index.html":
+			http.ServeFileFS(w, r, assets, "index.html")
+		case "display", "display/":
+			http.ServeFileFS(w, r, assets, "display.html")
+		case "admin", "admin/":
+			http.ServeFileFS(w, r, assets, "admin.html")
+		default:
+			if _, err := fs.Stat(assets, p); err != nil {
+				http.NotFound(w, r)
+				return
+			}
+			files.ServeHTTP(w, r)
+		}
+	})
+}
+
+func writeJSON(w http.ResponseWriter, code int, v any) {
+	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.WriteHeader(code)
+	_ = json.NewEncoder(w).Encode(v)
+}
+
+type statusRecorder struct {
+	http.ResponseWriter
+	status int
+}
+
+func (r *statusRecorder) WriteHeader(code int) {
+	r.status = code
+	r.ResponseWriter.WriteHeader(code)
+}
+
+func withRequestLog(next http.Handler, logger *slog.Logger) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		start := time.Now()
+		rec := &statusRecorder{ResponseWriter: w, status: http.StatusOK}
+		next.ServeHTTP(rec, r)
+		logger.Debug("http",
+			"method", r.Method,
+			"path", r.URL.Path,
+			"status", rec.status,
+			"dur", time.Since(start),
+		)
+	})
+}