Update dependencies and refactor random number generation

- Bump versions of several dependencies in Cargo.toml for improved functionality and security, including:
  - socket2 to 0.6
  - nix to 0.31
  - toml to 1.0
  - x509-parser to 0.18
  - dashmap to 6.1
  - rand to 0.10
  - reqwest to 0.13
  - notify to 8.2
  - ipnetwork to 0.21
  - webpki-roots to 1.0
  - criterion to 0.8
- Introduce `OnceLock` for secure random number generation in multiple modules to ensure thread safety and reduce overhead.
- Refactor random number generation calls to use the new `RngExt` trait methods for consistency and clarity.
- Add new PNG files for architectural documentation.

src/proxy/handshake.rs

@@ -17,7 +17,7 @@ use tracing::{debug, warn, trace};
 use zeroize::{Zeroize, Zeroizing};
 
 use crate::crypto::{sha256, AesCtr, SecureRandom};
-use rand::Rng;
+use rand::RngExt;
 use crate::protocol::constants::*;
 use crate::protocol::tls;
 use crate::stream::{FakeTlsReader, FakeTlsWriter, CryptoReader, CryptoWriter};