chore: Apply dashboard audit remediations, sync engine counts, update APIs

internal/domain/engines/ffi_sentinel_stub.go

@@ -0,0 +1,15 @@
+//go:build !sentinel_native
+
+package engines
+
+import "errors"
+
+// NativeSentinelCore is a dummy to make compilation pass when tag is missing.
+type NativeSentinelCore struct {
+	StubSentinelCore
+}
+
+// NewNativeSentinelCore returns an error when built without sentinel_native tag.
+func NewNativeSentinelCore() (*NativeSentinelCore, error) {
+	return nil, errors.New("sentinel_native build tag not provided; native engine disabled")
+}