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, 39 deletions

diff --git a/vendor/unicode-security/src/confusable_detection.rs b/vendor/unicode-security/src/confusable_detection.rs
deleted file mode 100644
index dd1a0d25..00000000
--- a/vendor/unicode-security/src/confusable_detection.rs
+++ /dev/null
@@ -1,39 +0,0 @@
-//! [Confusable detection](https://www.unicode.org/reports/tr39/#Confusable_Detection)
-
-use core::iter;
-
-enum OnceOrMore<T, I> {
-    Once(iter::Once<T>),
-    More(I),
-}
-
-impl<T, I> Iterator for OnceOrMore<T, I>
-where
-    I: Iterator<Item = T>,
-{
-    type Item = T;
-
-    fn next(&mut self) -> Option<T> {
-        use OnceOrMore::*;
-        match self {
-            Once(v) => v.next(),
-            More(i) => i.next(),
-        }
-    }
-}
-
-type StaticSliceIterCloned = core::iter::Cloned<core::slice::Iter<'static, char>>;
-
-fn char_prototype(c: char) -> OnceOrMore<char, StaticSliceIterCloned> {
-    use crate::tables::confusable_detection::char_confusable_prototype;
-    match char_confusable_prototype(c) {
-        None => OnceOrMore::Once(iter::once(c)),
-        Some(l) => OnceOrMore::More(l.iter().cloned()),
-    }
-}
-
-/// Calculate skeleton for string, as defined by UTS 39
-pub fn skeleton(s: &str) -> impl Iterator<Item = char> + '_ {
-    use unicode_normalization::UnicodeNormalization;
-    s.chars().nfd().flat_map(char_prototype).nfd()
-}