feat: migrate from Cedar to SpiceDB authorization system

This is a major architectural change that replaces the Cedar policy-based
authorization system with SpiceDB's relation-based authorization.

Key changes:

- Migrate from Rust to Go implementation
- Replace Cedar policies with SpiceDB schema and relationships
- Switch from envoy `ext_authz` with Cedar to SpiceDB permission checks
- Update build system and dependencies for Go ecosystem
- Maintain Envoy integration for external authorization

This change enables more flexible permission modeling through SpiceDB's
Google Zanzibar inspired relation-based system, supporting complex
hierarchical permissions that were difficult to express in Cedar.

Breaking change: Existing Cedar policies and Rust-based configuration
will no longer work and need to be migrated to SpiceDB schema.

1 files changed, 18 insertions, 0 deletions

diff --git a/vendor/github.com/authzed/grpcutil/util.go b/vendor/github.com/authzed/grpcutil/util.go
new file mode 100644
index 00000000..65bb3bd5
--- /dev/null
+++ b/vendor/github.com/authzed/grpcutil/util.go
@@ -0,0 +1,18 @@
+package grpcutil
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+// RequireStatus asserts that an error is a gRPC error and returns the expected
+// status code.
+func RequireStatus(t *testing.T, expected codes.Code, err error) {
+	require.Error(t, err)
+	errStatus, ok := status.FromError(err)
+	require.True(t, ok)
+	require.Equal(t, expected, errStatus.Code())
+}