Refactor proxy and transport modules for improved safety and performance

- Enhanced linting rules in `src/proxy/mod.rs` to enforce stricter code quality checks in production.
- Updated hash functions in `src/proxy/middle_relay.rs` for better efficiency.
- Added new security tests in `src/proxy/tests/middle_relay_stub_completion_security_tests.rs` to validate desynchronization behavior.
- Removed ignored test stubs in `src/proxy/tests/middle_relay_security_tests.rs` to clean up the test suite.
- Improved error handling and code readability in various transport modules, including `src/transport/middle_proxy/config_updater.rs` and `src/transport/middle_proxy/pool.rs`.
- Introduced new padding functions in `src/stream/frame_stream_padding_security_tests.rs` to ensure consistent behavior across different implementations.
- Adjusted TLS stream validation in `src/stream/tls_stream.rs` for better boundary checking.
- General code cleanup and dead code elimination across multiple files to enhance maintainability.

src/proxy/handshake.rs

@@ -626,7 +626,7 @@ where
     let cached = if config.censorship.tls_emulation {
         if let Some(cache) = tls_cache.as_ref() {
             let selected_domain = if let Some(sni) = client_sni.as_ref() {
-                if cache.contains_domain(&sni).await {
+                if cache.contains_domain(sni).await {
                     sni.clone()
                 } else {
                     config.censorship.tls_domain.clone()
@@ -954,7 +954,6 @@ pub fn encrypt_tg_nonce_with_ciphers(nonce: &[u8; HANDSHAKE_LEN]) -> (Vec<u8>, A
 }
 
 /// Encrypt nonce for sending to Telegram (legacy function for compatibility)
-
 pub fn encrypt_tg_nonce(nonce: &[u8; HANDSHAKE_LEN]) -> Vec<u8> {
     let (encrypted, _, _) = encrypt_tg_nonce_with_ciphers(nonce);
     encrypted