feat: add initial setup wizard, workload insights, and policy audit mode

Add setup wizard with status tracking via SystemSetting model, implement /setup/status and /setup/complete endpoints to create initial admin user and optional cluster configuration, add workload insights endpoint with traffic analysis and policy matching including audit mode detection, implement enforcement_mode property on Policy model with audit/enforced states, add Modal component for dialogs, create SetupWizard page with multi

backend/app/models/domain.py

@@ -49,6 +49,13 @@ class TimestampMixin:
     updated_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
 
 
+class SystemSetting(Base, TimestampMixin):
+    __tablename__ = "system_settings"
+
+    key: Mapped[str] = mapped_column(String(100), primary_key=True)
+    value: Mapped[dict] = mapped_column(JSON, default=dict)
+
+
 class User(Base, TimestampMixin):
     __tablename__ = "users"
 
@@ -212,6 +219,10 @@ class Policy(Base, TimestampMixin):
     definition: Mapped[dict] = mapped_column(JSON, default=dict)
     last_compiled: Mapped[dict | None] = mapped_column(JSON)
 
+    @property
+    def enforcement_mode(self) -> str:
+        return (self.definition or {}).get("enforcement_mode", "enforced")
+
 
 class ServiceCatalogItem(Base, TimestampMixin):
     __tablename__ = "service_catalog"
@@ -251,4 +262,3 @@ class AuditLog(Base):
     user_agent: Mapped[str | None] = mapped_column(String(512))
     result: Mapped[str] = mapped_column(String(100), default="success")
     error_text: Mapped[str | None] = mapped_column(Text)
-