Apply clippy fixes for code quality

Clippy Fixes Applied:
- Removed unused imports
- Fixed manual implementation of .is_multiple_of()
- Fixed unnecessary_sort_by suggestions
- Added missing Ipv4Addr imports

Files Modified:
- forward_acl.rs: Add Ipv4Addr import
- known_hosts.rs: Add Ipv4Addr import
- Various files: Remove unused imports

Build: ✅ markbase-core
Tests: 495 passed

markbase-core/src/ctdb/protocol.rs

@@ -1,5 +1,4 @@
-use byteorder::{BigEndian, LittleEndian, ReadBytesExt, WriteBytesExt};
-use std::io::{self, Cursor, Read, Write};
+use std::io::{self, Read, Write};
 use std::net::TcpStream;
 
 pub const CTDB_MAGIC: u32 = 0x43544442;