cyi-box: Memphis-style toolbox admin platform

Go(fun)+SQLite backend, Vue 3 frontend. Modules: dashboard, pay gateway
(Epay-compatible + CDK stock), license/card system (per-app appid, domain
binding), AI memory bank with built-in MCP server (/mcp, FTS5 search,
signed read links), server SSH monitor + terminal + SFTP, proxy pool with
protocol-level alive checks, DB manager (mysql/pg/sqlite + SQL
autocomplete + import/export), disk share, vault (AES-GCM + TOTP),
bookmarks, dev tools.

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backend/internal/store/setting.go

@@ -0,0 +1,20 @@
+package store
+
+import (
+	"database/sql"
+	"errors"
+
+	"github.com/cyi-cc/cyi-box/backend/internal/db"
+)
+
+func (s *Store) GetSetting(key string) (string, error) {
+	v, err := s.q.GetSetting(storeCtx, key)
+	if errors.Is(err, sql.ErrNoRows) {
+		return "", nil
+	}
+	return v, err
+}
+
+func (s *Store) SetSetting(key, value string) error {
+	return s.q.UpsertSetting(storeCtx, db.UpsertSettingParams{K: key, V: value})
+}