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, 75 deletions

diff --git a/vendor/time/src/interop/offsetdatetime_systemtime.rs b/vendor/time/src/interop/offsetdatetime_systemtime.rs
deleted file mode 100644
index 21a5d7f1..00000000
--- a/vendor/time/src/interop/offsetdatetime_systemtime.rs
+++ /dev/null
@@ -1,75 +0,0 @@
-use core::cmp::Ordering;
-use core::ops::Sub;
-use std::time::SystemTime;
-
-use crate::{Duration, OffsetDateTime};
-
-impl Sub<SystemTime> for OffsetDateTime {
-    type Output = Duration;
-
-    /// # Panics
-    ///
-    /// This may panic if an overflow occurs.
-    fn sub(self, rhs: SystemTime) -> Self::Output {
-        self - Self::from(rhs)
-    }
-}
-
-impl Sub<OffsetDateTime> for SystemTime {
-    type Output = Duration;
-
-    /// # Panics
-    ///
-    /// This may panic if an overflow occurs.
-    fn sub(self, rhs: OffsetDateTime) -> Self::Output {
-        OffsetDateTime::from(self) - rhs
-    }
-}
-
-impl PartialEq<SystemTime> for OffsetDateTime {
-    fn eq(&self, rhs: &SystemTime) -> bool {
-        self == &Self::from(*rhs)
-    }
-}
-
-impl PartialEq<OffsetDateTime> for SystemTime {
-    fn eq(&self, rhs: &OffsetDateTime) -> bool {
-        &OffsetDateTime::from(*self) == rhs
-    }
-}
-
-impl PartialOrd<SystemTime> for OffsetDateTime {
-    fn partial_cmp(&self, other: &SystemTime) -> Option<Ordering> {
-        self.partial_cmp(&Self::from(*other))
-    }
-}
-
-impl PartialOrd<OffsetDateTime> for SystemTime {
-    fn partial_cmp(&self, other: &OffsetDateTime) -> Option<Ordering> {
-        OffsetDateTime::from(*self).partial_cmp(other)
-    }
-}
-
-impl From<SystemTime> for OffsetDateTime {
-    fn from(system_time: SystemTime) -> Self {
-        match system_time.duration_since(SystemTime::UNIX_EPOCH) {
-            Ok(duration) => Self::UNIX_EPOCH + duration,
-            Err(err) => Self::UNIX_EPOCH - err.duration(),
-        }
-    }
-}
-
-impl From<OffsetDateTime> for SystemTime {
-    fn from(datetime: OffsetDateTime) -> Self {
-        let duration = datetime - OffsetDateTime::UNIX_EPOCH;
-
-        if duration.is_zero() {
-            Self::UNIX_EPOCH
-        } else if duration.is_positive() {
-            Self::UNIX_EPOCH + duration.unsigned_abs()
-        } else {
-            debug_assert!(duration.is_negative());
-            Self::UNIX_EPOCH - duration.unsigned_abs()
-        }
-    }
-}