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, 33 deletions

diff --git a/vendor/thiserror/build/probe.rs b/vendor/thiserror/build/probe.rs
deleted file mode 100644
index ee126d45..00000000
--- a/vendor/thiserror/build/probe.rs
+++ /dev/null
@@ -1,33 +0,0 @@
-// This code exercises the surface area that we expect of the Error generic
-// member access API. If the current toolchain is able to compile it, then
-// thiserror is able to provide backtrace support.
-
-#![no_std]
-#![feature(error_generic_member_access)]
-
-use core::error::{Error, Request};
-use core::fmt::{self, Debug, Display};
-
-struct MyError(Thing);
-struct Thing;
-
-impl Debug for MyError {
-    fn fmt(&self, _formatter: &mut fmt::Formatter) -> fmt::Result {
-        unimplemented!()
-    }
-}
-
-impl Display for MyError {
-    fn fmt(&self, _formatter: &mut fmt::Formatter) -> fmt::Result {
-        unimplemented!()
-    }
-}
-
-impl Error for MyError {
-    fn provide<'a>(&'a self, request: &mut Request<'a>) {
-        request.provide_ref(&self.0);
-    }
-}
-
-// Include in sccache cache key.
-const _: Option<&str> = option_env!("RUSTC_BOOTSTRAP");