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, 0 insertions, 26 deletions

diff --git a/vendor/dyn-clone/examples/readme.rs b/vendor/dyn-clone/examples/readme.rs
deleted file mode 100644
index 41682cd1..00000000
--- a/vendor/dyn-clone/examples/readme.rs
+++ /dev/null
@@ -1,26 +0,0 @@
-use dyn_clone::DynClone;
-
-trait MyTrait: DynClone {
-    fn recite(&self);
-}
-
-impl MyTrait for String {
-    fn recite(&self) {
-        println!("{} ♫", self);
-    }
-}
-
-fn main() {
-    let line = "The slithy structs did gyre and gimble the namespace";
-
-    // Build a trait object holding a String.
-    // This requires String to implement MyTrait and std::clone::Clone.
-    let x: Box<dyn MyTrait> = Box::new(String::from(line));
-
-    x.recite();
-
-    // The type of x2 is a Box<dyn MyTrait> cloned from x.
-    let x2 = dyn_clone::clone_box(&*x);
-
-    x2.recite();
-}