feat(gateway): wire real services into Gateway API handlers

- Router accepts full Dependencies (memory/voice/orchestrator/WShub)
- Memory API: CRUD + search endpoints with PostgreSQL persistence
- Voice API: STT/TTS endpoints
- Admin dashboard: real uptime + service status
- WebSocket chat: routes to AI-Core orchestrator pipeline
- APIAdapter bridges memory domain model to REST interface
- Smoke test: memory CRUD + session creation verified

backend/services/memory/adapter.go

@@ -0,0 +1,86 @@
+package memory
+
+import "context"
+
+// APIAdapter adapts the memory Service to a simplified API interface.
+// This bridges between the rich domain model and the Gateway's REST handler expectations.
+type APIAdapter struct {
+	svc *Service
+}
+
+// APIEntry is the simplified memory entry for REST API responses.
+type APIEntry struct {
+	ID       string   `json:"id"`
+	UserID   string   `json:"user_id"`
+	Content  string   `json:"content"`
+	Summary  string   `json:"summary"`
+	Keywords []string `json:"keywords"`
+	Category string   `json:"category"`
+	Priority float64  `json:"priority"`
+}
+
+// NewAPIAdapter wraps a Service for REST API consumption.
+func NewAPIAdapter(svc *Service) *APIAdapter {
+	return &APIAdapter{svc: svc}
+}
+
+func (a *APIAdapter) Search(ctx context.Context, userID, query string, limit int) (any, error) {
+	memories, err := a.svc.Search(ctx, SearchQuery{UserID: userID, Query: query, Limit: limit})
+	if err != nil {
+		return nil, err
+	}
+	result := make([]APIEntry, len(memories))
+	for i, m := range memories {
+		result[i] = toEntry(m)
+	}
+	return result, nil
+}
+
+func (a *APIAdapter) List(ctx context.Context, userID string, limit int) (any, error) {
+	memories, err := a.svc.List(ctx, userID, limit)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]APIEntry, len(memories))
+	for i, m := range memories {
+		result[i] = toEntry(m)
+	}
+	return result, nil
+}
+
+func (a *APIAdapter) Add(ctx context.Context, userID, content, category string, priority float64) (any, error) {
+	m, err := a.svc.Add(ctx, userID, "", content, category, priority)
+	if err != nil {
+		return nil, err
+	}
+	e := toEntry(*m)
+	return &e, nil
+}
+
+func (a *APIAdapter) Get(ctx context.Context, id string) (any, error) {
+	m, err := a.svc.GetByID(ctx, id)
+	if err != nil {
+		return nil, err
+	}
+	e := toEntry(*m)
+	return &e, nil
+}
+
+func (a *APIAdapter) Delete(ctx context.Context, id string) error {
+	return a.svc.Delete(ctx, id)
+}
+
+func toEntry(m Memory) APIEntry {
+	return APIEntry{
+		ID:       m.ID,
+		UserID:   m.UserID,
+		Content:  m.Content,
+		Summary:  m.Summary,
+		Keywords: m.Keywords,
+		Category: m.Category,
+		Priority: m.Priority,
+	}
+}
+
+// Ensure we use context
+var _ = context.Background