Unify SHA256 hash and hex usages (#687)

bitchatTests/NostrProtocolTests.swift

@@ -6,16 +6,10 @@
 //
 
 import XCTest
-import CryptoKit
 @testable import bitchat
 
 final class NostrProtocolTests: XCTestCase {
     
-    override func setUp() {
-        super.setUp()
-        // SecureLogger is always enabled
-    }
-    
     func testNIP17MessageRoundTrip() throws {
         // Create sender and recipient identities
         let sender = try NostrIdentity.generate()