feat: Go backend, enhanced search, new widgets, Docker deploy

Major changes:
- Add Go backend (backend/) with microservices architecture
- Enhanced master-agents-svc: reranker, content-classifier, stealth-crawler,
  proxy-manager, media-search, fastClassifier, language detection
- New web-svc widgets: KnowledgeCard, ProductCard, ProfileCard, VideoCard,
  UnifiedCard, CardGallery, InlineImageGallery, SourcesPanel, RelatedQuestions
- Improved discover-svc with discover-db integration
- Docker deployment improvements (Caddyfile, vendor.sh, BUILD.md)
- Library-svc: project_id schema migration
- Remove deprecated finance-svc and travel-svc
- Localization improvements across services

Made-with: Cursor

backend/internal/computer/connectors/connector.go

@@ -0,0 +1,104 @@
+package connectors
+
+import (
+	"context"
+	"errors"
+	"sync"
+)
+
+type Connector interface {
+	ID() string
+	Name() string
+	Description() string
+	Execute(ctx context.Context, action string, params map[string]interface{}) (interface{}, error)
+	GetActions() []Action
+	Validate(params map[string]interface{}) error
+}
+
+type Action struct {
+	Name        string                 `json:"name"`
+	Description string                 `json:"description"`
+	Schema      map[string]interface{} `json:"schema"`
+	Required    []string               `json:"required"`
+}
+
+type ConnectorHub struct {
+	connectors map[string]Connector
+	mu         sync.RWMutex
+}
+
+func NewConnectorHub() *ConnectorHub {
+	return &ConnectorHub{
+		connectors: make(map[string]Connector),
+	}
+}
+
+func (h *ConnectorHub) Register(connector Connector) {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	h.connectors[connector.ID()] = connector
+}
+
+func (h *ConnectorHub) Unregister(id string) {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	delete(h.connectors, id)
+}
+
+func (h *ConnectorHub) Get(id string) (Connector, error) {
+	h.mu.RLock()
+	defer h.mu.RUnlock()
+
+	connector, ok := h.connectors[id]
+	if !ok {
+		return nil, errors.New("connector not found: " + id)
+	}
+	return connector, nil
+}
+
+func (h *ConnectorHub) List() []Connector {
+	h.mu.RLock()
+	defer h.mu.RUnlock()
+
+	result := make([]Connector, 0, len(h.connectors))
+	for _, c := range h.connectors {
+		result = append(result, c)
+	}
+	return result
+}
+
+func (h *ConnectorHub) Execute(ctx context.Context, connectorID, action string, params map[string]interface{}) (interface{}, error) {
+	connector, err := h.Get(connectorID)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := connector.Validate(params); err != nil {
+		return nil, err
+	}
+
+	return connector.Execute(ctx, action, params)
+}
+
+type ConnectorInfo struct {
+	ID          string   `json:"id"`
+	Name        string   `json:"name"`
+	Description string   `json:"description"`
+	Actions     []Action `json:"actions"`
+}
+
+func (h *ConnectorHub) GetInfo() []ConnectorInfo {
+	h.mu.RLock()
+	defer h.mu.RUnlock()
+
+	result := make([]ConnectorInfo, 0, len(h.connectors))
+	for _, c := range h.connectors {
+		result = append(result, ConnectorInfo{
+			ID:          c.ID(),
+			Name:        c.Name(),
+			Description: c.Description(),
+			Actions:     c.GetActions(),
+		})
+	}
+	return result
+}