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- Remove outdated dependencies and update dependency versions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

remote/find_remote.rs

@@ -11,6 +11,7 @@ pub fn find_remote_repository(
             exists: false,
         });
     }
+    crate::sanitize::validate_remote_url(&request.remote_url)?;
 
     let output = std::process::Command::new("git")
         .args(["ls-remote", "--symref", &request.remote_url])
@@ -78,6 +79,11 @@ pub fn find_remote_repository(
 pub fn find_remote_root_ref(
     request: FindRemoteRootRefRequest,
 ) -> GitResult<FindRemoteRootRefResponse> {
+    if request.remote_url.is_empty() {
+        return Ok(FindRemoteRootRefResponse::default());
+    }
+    crate::sanitize::validate_remote_url(&request.remote_url)?;
+
     let output = std::process::Command::new("git")
         .args(["ls-remote", "--symref", &request.remote_url, "HEAD"])
         .stdout(std::process::Stdio::piped())
@@ -87,6 +93,9 @@ pub fn find_remote_root_ref(
             status_code: None,
             stderr: e.to_string(),
         })?;
+    if !output.status.success() {
+        return Ok(FindRemoteRootRefResponse::default());
+    }
 
     let stdout = String::from_utf8_lossy(&output.stdout);
     for line in stdout.lines() {

remote/mirror.rs

@@ -20,7 +20,7 @@ impl GitBare {
             crate::sanitize::validate_refspec(rs)?;
         }
 
-        let remote_check = std::process::Command::new("git")
+        let remote_exists = std::process::Command::new("git")
             .args([
                 "--git-dir",
                 &self.bare_dir.to_string_lossy(),
@@ -28,38 +28,33 @@ impl GitBare {
                 "get-url",
                 remote_name,
             ])
-            .output();
+            .output()
+            .map(|output| output.status.success())
+            .unwrap_or(false);
 
-        if remote_check.is_err() || !remote_check.unwrap().status.success() {
-            std::process::Command::new("git")
-                .args([
-                    "--git-dir",
-                    &self.bare_dir.to_string_lossy(),
-                    "remote",
-                    "add",
-                    remote_name,
-                    &request.remote_url,
-                ])
-                .output()
-                .map_err(|e| crate::error::GitError::CommandFailed {
-                    status_code: None,
-                    stderr: e.to_string(),
-                })?;
-        } else {
-            std::process::Command::new("git")
-                .args([
-                    "--git-dir",
-                    &self.bare_dir.to_string_lossy(),
-                    "remote",
-                    "set-url",
-                    remote_name,
-                    &request.remote_url,
-                ])
-                .output()
-                .map_err(|e| crate::error::GitError::CommandFailed {
-                    status_code: None,
-                    stderr: e.to_string(),
-                })?;
+        let remote_command = if remote_exists { "set-url" } else { "add" };
+        let remote_output = std::process::Command::new("git")
+            .args([
+                "--git-dir",
+                &self.bare_dir.to_string_lossy(),
+                "remote",
+                remote_command,
+                remote_name,
+                &request.remote_url,
+            ])
+            .output()
+            .map_err(|e| crate::error::GitError::CommandFailed {
+                status_code: None,
+                stderr: e.to_string(),
+            })?;
+
+        if !remote_output.status.success() {
+            return Ok(UpdateRemoteMirrorResponse {
+                ok: false,
+                error: String::from_utf8_lossy(&remote_output.stderr)
+                    .trim()
+                    .to_string(),
+            });
         }
 
         let mut fetch_args = vec![
@@ -156,7 +151,7 @@ impl GitBare {
             .unwrap_or(false);
 
         if !exists {
-            std::process::Command::new("git")
+            let remote_output = std::process::Command::new("git")
                 .args([
                     "--git-dir",
                     &self.bare_dir.to_string_lossy(),
@@ -170,6 +165,15 @@ impl GitBare {
                     status_code: None,
                     stderr: e.to_string(),
                 })?;
+
+            if !remote_output.status.success() {
+                return Ok(FetchRemoteResponse {
+                    ok: false,
+                    error: String::from_utf8_lossy(&remote_output.stderr)
+                        .trim()
+                        .to_string(),
+                });
+            }
         }
 
         let mut args = vec![