Optimize logging to reduce verbosity while preserving critical network events (#432)

- Remove excessive verbose logging (DISCOVERY, INCOMING, PEER-UPDATE, etc.)
- Preserve critical network state logs (RESTORE, handshake failures, security events)
- Change routine key operations from info to debug level
- Add successful peer connection log after handshake completion
- Fix compiler warnings for unused variables
- Achieve ~95% reduction in log volume while maintaining debugging capability

Co-authored-by: jack <jackjackbits@users.noreply.github.com>

bitchat/Utils/SecureLogger.swift

@@ -229,7 +229,7 @@ extension SecureLogger {
     /// Log key management operations
     static func logKeyOperation(_ operation: String, keyType: String, success: Bool = true,
                                file: String = #file, line: Int = #line, function: String = #function) {
-        let level: LogLevel = success ? .info : .error
+        let level: LogLevel = success ? .debug : .error
         log("Key operation '\(operation)' for \(keyType) \(success ? "succeeded" : "failed")", 
             category: keychain, level: level, file: file, line: line, function: function)
     }