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, 45 deletions

diff --git a/vendor/fixedbitset/src/range.rs b/vendor/fixedbitset/src/range.rs
deleted file mode 100644
index 9b385c42..00000000
--- a/vendor/fixedbitset/src/range.rs
+++ /dev/null
@@ -1,45 +0,0 @@
-use core::ops::{Range, RangeFrom, RangeFull, RangeTo};
-
-// Taken from https://github.com/bluss/odds/blob/master/src/range.rs.
-
-/// **IndexRange** is implemented by Rust's built-in range types, produced
-/// by range syntax like `..`, `a..`, `..b` or `c..d`.
-pub trait IndexRange<T = usize> {
-    #[inline]
-    /// Start index (inclusive)
-    fn start(&self) -> Option<T> {
-        None
-    }
-    #[inline]
-    /// End index (exclusive)
-    fn end(&self) -> Option<T> {
-        None
-    }
-}
-
-impl<T> IndexRange<T> for RangeFull {}
-
-impl<T: Copy> IndexRange<T> for RangeFrom<T> {
-    #[inline]
-    fn start(&self) -> Option<T> {
-        Some(self.start)
-    }
-}
-
-impl<T: Copy> IndexRange<T> for RangeTo<T> {
-    #[inline]
-    fn end(&self) -> Option<T> {
-        Some(self.end)
-    }
-}
-
-impl<T: Copy> IndexRange<T> for Range<T> {
-    #[inline]
-    fn start(&self) -> Option<T> {
-        Some(self.start)
-    }
-    #[inline]
-    fn end(&self) -> Option<T> {
-        Some(self.end)
-    }
-}