package pluginhost import (	"context"	"strconv"	"sync"	"sync/atomic") type callbackContextRegistry struct {	next     atomic.Uint64	mu       sync.RWMutex	contexts map[string]context.Context} func newCallbackContextRegistry() *callbackContextRegistry {	return &callbackContextRegistry{contexts: make(map[string]context.Context)}} func (r *callbackContextRegistry) open(ctx context.Context) (string, func()) {	if r == nil {		return "", func() {}	}	if ctx == nil {		ctx = context.Background()	}	id := strconv.FormatUint(r.next.Add(1), 10)	r.mu.Lock()	r.contexts[id] = ctx	r.mu.Unlock() 	var once sync.Once	return id, func() {		once.Do(func() {			r.mu.Lock()			delete(r.contexts, id)			r.mu.Unlock()		})	}} func (r *callbackContextRegistry) resolve(id string, fallback context.Context) context.Context {	if fallback == nil {		fallback = context.Background()	}	if r == nil || id == "" {		return fallback	}	r.mu.RLock()	ctx := r.contexts[id]	r.mu.RUnlock()	if ctx == nil {		return fallback	}	return ctx} func (h *Host) openCallbackContext(ctx context.Context) (string, func()) {	if h == nil || h.callbackContexts == nil {		return "", func() {}	}	return h.callbackContexts.open(ctx)} func (h *Host) resolveCallbackContext(id string, fallback context.Context) context.Context {	if h == nil || h.callbackContexts == nil {		if fallback == nil {			return context.Background()		}		return fallback	}	return h.callbackContexts.resolve(id, fallback)}