refactor(cache): redesign cache system with structured keys and improved performance

- Add repo_path parameter to cached_response and cached_vec_response functions
- Implement structured cache key format with namespace, repo_path, and request proto
- Replace global cache with Moka in-memory cache using weight-based eviction
- Set 256MB memory cap with 10-minute TTL and 2-minute TTI policy
- Add metrics collection for cache operations and evictions
- Implement efficient repo-scoped invalidation using key structure
- Add detailed documentation comments explaining cache architecture
- Remove outdated dependencies and update dependency versions
- Add error handling for encoding failures in cache operations
- Optimize Vec responses with length-delimited encoding and pre-allocation

tree/mod.rs

@@ -10,7 +10,10 @@ pub(crate) fn resolve_revision(
     sel: &Option<pb::ObjectSelector>,
 ) -> Result<String, crate::error::GitError> {
     match sel.as_ref().and_then(|s| s.selector.as_ref()) {
-        Some(object_selector::Selector::Oid(oid)) => Ok(oid.hex.clone()),
+        Some(object_selector::Selector::Oid(oid)) => {
+            crate::sanitize::validate_oid_hex(&oid.hex)?;
+            Ok(oid.hex.clone())
+        }
         Some(object_selector::Selector::Revision(name)) => {
             crate::sanitize::validate_revision(&name.revision)?;
             Ok(name.revision.clone())