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.

3 files changed, 111 insertions, 0 deletions

diff --git a/vendor/github.com/google/yamlfmt/formatters/basic/features/check.go b/vendor/github.com/google/yamlfmt/formatters/basic/features/check.go
new file mode 100644
index 00000000..368de5ce
--- /dev/null
+++ b/vendor/github.com/google/yamlfmt/formatters/basic/features/check.go
@@ -0,0 +1,37 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package features
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/google/yamlfmt/pkg/yaml"
+)
+
+func Check(n yaml.Node) error {
+	if n.Kind == yaml.AliasNode {
+		return errors.New("alias node found")
+	}
+	if n.Anchor != "" {
+		return fmt.Errorf("node references anchor %q", n.Anchor)
+	}
+	for _, c := range n.Content {
+		if err := Check(*c); err != nil {
+			return err
+		}
+	}
+	return nil
+}
diff --git a/vendor/github.com/google/yamlfmt/formatters/basic/features/force_sequence.go b/vendor/github.com/google/yamlfmt/formatters/basic/features/force_sequence.go
new file mode 100644
index 00000000..f3f956c5
--- /dev/null
+++ b/vendor/github.com/google/yamlfmt/formatters/basic/features/force_sequence.go
@@ -0,0 +1,43 @@
+// Copyright 2025 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package features
+
+import "github.com/google/yamlfmt/pkg/yaml"
+
+type SequenceStyle string
+
+const (
+	SequenceStyleBlock SequenceStyle = "block"
+	SequenceStyleFlow  SequenceStyle = "flow"
+)
+
+func FeatureForceSequenceStyle(style SequenceStyle) YAMLFeatureFunc {
+	var styleVal yaml.Style
+	if style == SequenceStyleFlow {
+		styleVal = yaml.FlowStyle
+	}
+	var forceStyle YAMLFeatureFunc
+	forceStyle = func(n yaml.Node) error {
+		var err error
+		for _, c := range n.Content {
+			if c.Kind == yaml.SequenceNode {
+				c.Style = styleVal
+			}
+			err = forceStyle(*c)
+		}
+		return err
+	}
+	return forceStyle
+}
diff --git a/vendor/github.com/google/yamlfmt/formatters/basic/features/yaml_feature.go b/vendor/github.com/google/yamlfmt/formatters/basic/features/yaml_feature.go
new file mode 100644
index 00000000..2657a539
--- /dev/null
+++ b/vendor/github.com/google/yamlfmt/formatters/basic/features/yaml_feature.go
@@ -0,0 +1,31 @@
+// Copyright 2025 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package features
+
+import "github.com/google/yamlfmt/pkg/yaml"
+
+// These features will directly use the `yaml.Node` type and
+// as such are specific to this formatter.
+type YAMLFeatureFunc func(yaml.Node) error
+type YAMLFeatureList []YAMLFeatureFunc
+
+func (y YAMLFeatureList) ApplyFeatures(node yaml.Node) error {
+	for _, f := range y {
+		if err := f(node); err != nil {
+			return err
+		}
+	}
+	return nil
+}