feat(customers): add dashboard and customer management

backend/hermes/app/api/dashboard.py

@@ -0,0 +1,80 @@
+import logging
+
+from fastapi import APIRouter, Depends
+from sqlalchemy import func, select
+from sqlalchemy.orm import Session
+
+from app.core.rbac import get_user_permission_names, require_permission
+from app.db.database import get_db
+from app.models.rbac import Role
+from app.models.user import User
+from app.repositories.customer_repository import CustomerRepository
+from app.repositories.user_repository import UserRepository
+from app.schemas.dashboard import DashboardSummary, EmptyWidget, MetricCard
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(
+    prefix="/dashboard",
+    tags=["Dashboard"],
+)
+
+
+@router.get("/summary", response_model=DashboardSummary)
+def get_dashboard_summary(
+    db: Session = Depends(get_db),
+    current_user: User = Depends(require_permission("dashboard.read")),
+):
+    permissions = get_user_permission_names(current_user)
+    customers: list[MetricCard] = []
+    latest_customers = []
+    users: list[MetricCard] = []
+    roles: list[MetricCard] = []
+
+    if "customers.read" in permissions:
+        customers = [
+            MetricCard(label="Kunden", value=CustomerRepository.count_all(db)),
+            MetricCard(label="Aktive Kunden", value=CustomerRepository.count_active(db)),
+            MetricCard(label="Neue Kunden", value=CustomerRepository.count_recent(db)),
+        ]
+        latest_customers = CustomerRepository.get_latest(db)
+
+    if "users.read" in permissions:
+        all_users = UserRepository.get_all(db)
+        users = [
+            MetricCard(label="Benutzer", value=len(all_users)),
+            MetricCard(label="Aktive Benutzer", value=len([user for user in all_users if user.is_active])),
+        ]
+
+    if "roles.read" in permissions:
+        roles = [
+            MetricCard(
+                label="Rollen",
+                value=db.scalar(select(func.count(Role.id))) or 0,
+            )
+        ]
+
+    logger.info("dashboard.summary", extra={"actor_user_id": current_user.id})
+
+    return DashboardSummary(
+        customers=customers,
+        latest_customers=latest_customers,
+        users=users,
+        roles=roles,
+        activities=EmptyWidget(
+            title="Letzte Aktivitäten",
+            message="Noch keine Aktivitäten vorhanden.",
+        ),
+        tasks=EmptyWidget(
+            title="Offene Aufgaben",
+            message="Noch keine Aufgaben vorhanden.",
+        ),
+        tickets=EmptyWidget(
+            title="Offene Tickets",
+            message="Noch keine Tickets vorhanden.",
+        ),
+        projects=EmptyWidget(
+            title="Projekte",
+            message="Noch keine Projektdaten vorhanden.",
+        ),
+    )