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, 36 deletions

diff --git a/vendor/async-trait/tests/executor/mod.rs b/vendor/async-trait/tests/executor/mod.rs
deleted file mode 100644
index 912fb798..00000000
--- a/vendor/async-trait/tests/executor/mod.rs
+++ /dev/null
@@ -1,36 +0,0 @@
-use std::future::Future;
-use std::pin::Pin;
-use std::ptr;
-use std::task::{Context, Poll, RawWaker, RawWakerVTable, Waker};
-
-// Executor for a future that resolves immediately (test only).
-#[allow(clippy::missing_panics_doc)]
-pub fn block_on_simple<F: Future>(mut fut: F) -> F::Output {
-    unsafe fn clone(_null: *const ()) -> RawWaker {
-        unimplemented!()
-    }
-
-    unsafe fn wake(_null: *const ()) {
-        unimplemented!()
-    }
-
-    unsafe fn wake_by_ref(_null: *const ()) {
-        unimplemented!()
-    }
-
-    unsafe fn drop(_null: *const ()) {}
-
-    let data = ptr::null();
-    let vtable = &RawWakerVTable::new(clone, wake, wake_by_ref, drop);
-    let raw_waker = RawWaker::new(data, vtable);
-    let waker = unsafe { Waker::from_raw(raw_waker) };
-    let mut cx = Context::from_waker(&waker);
-
-    // fut does not move until it gets dropped.
-    let fut = unsafe { Pin::new_unchecked(&mut fut) };
-
-    match fut.poll(&mut cx) {
-        Poll::Ready(output) => output,
-        Poll::Pending => panic!("future did not resolve immediately"),
-    }
-}