feat: Auto Read-only API-Key bei Kunden-Erstellung

- createCustomer erstellt automatisch einen customer-scoped Read-only Key
- Response gibt Customer + neuen API-Key zurueck
- Bestehende 4 Kunden Keys nachtraglich erstellt

backend/api/customers.go

@@ -1,11 +1,28 @@
 package api
 
 import (
+	"crypto/rand"
+	"encoding/hex"
 	"encoding/json"
+	"fmt"
+	"log"
 	"net/http"
 	"strconv"
+
+	"github.com/cynfo/rmm-backend/db"
 )
 
+// generateCustomerAPIKey erstellt automatisch einen Read-only Key fuer einen Kunden
+func generateCustomerAPIKey(database *db.Database, customerID int, number, name string) (*db.APIKey, error) {
+	b := make([]byte, 16)
+	if _, err := rand.Read(b); err != nil {
+		return nil, err
+	}
+	key := hex.EncodeToString(b)
+	keyName := fmt.Sprintf("Read-only — %s %s", number, name)
+	return database.CreateAPIKey(keyName, key, "read", &customerID)
+}
+
 // GET /api/v1/customers
 func (h *Handler) listCustomers(w http.ResponseWriter, r *http.Request) {
 	customers, err := h.db.GetCustomers()
@@ -31,8 +48,22 @@ func (h *Handler) createCustomer(w http.ResponseWriter, r *http.Request) {
 		writeError(w, http.StatusInternalServerError, "Kunde anlegen fehlgeschlagen")
 		return
 	}
+
+	// Automatisch einen Read-only API-Key fuer den neuen Kunden erstellen
+	apiKey, keyErr := generateCustomerAPIKey(h.db, c.ID, req.Number, req.Name)
+	if keyErr != nil {
+		log.Printf("Auto-API-Key fuer Kunde %s fehlgeschlagen: %v", req.Number, keyErr)
+	}
+
 	h.auditLog(r, "customer.create", "customer", req.Number, req.Name, "")
-	writeJSON(w, http.StatusCreated, c)
+
+	resp := map[string]interface{}{
+		"customer": c,
+	}
+	if apiKey != nil {
+		resp["api_key"] = apiKey
+	}
+	writeJSON(w, http.StatusCreated, resp)
 }
 
 // GET /api/v1/customers/{id}