feat(protocols): refactor protocol utilities into centralized protocols module

ts/detection/utils/buffer-utils.ts

@@ -2,6 +2,9 @@
  * Buffer manipulation utilities for protocol detection
  */
 
+// Import from protocols
+import { HttpParser } from '../../protocols/http/index.js';
+
 /**
  * BufferAccumulator class for handling fragmented data
  */
@@ -101,33 +104,8 @@ export function findSequence(buffer: Buffer, sequence: Buffer, startOffset = 0):
  * Extract a line from buffer (up to CRLF or LF)
  */
 export function extractLine(buffer: Buffer, startOffset = 0): { line: string; nextOffset: number } | null {
-  let lineEnd = -1;
-  let skipBytes = 1;
-  
-  // Look for CRLF first
-  const crlfPos = findSequence(buffer, Buffer.from('\r\n'), startOffset);
-  if (crlfPos !== -1) {
-    lineEnd = crlfPos;
-    skipBytes = 2;
-  } else {
-    // Look for LF only
-    for (let i = startOffset; i < buffer.length; i++) {
-      if (buffer[i] === 0x0A) { // LF
-        lineEnd = i;
-        break;
-      }
-    }
-  }
-  
-  if (lineEnd === -1) {
-    return null;
-  }
-  
-  const line = buffer.slice(startOffset, lineEnd).toString('utf8');
-  return {
-    line,
-    nextOffset: lineEnd + skipBytes
-  };
+  // Delegate to protocol parser
+  return HttpParser.extractLine(buffer, startOffset);
 }
 
 /**
@@ -158,17 +136,6 @@ export function safeSlice(buffer: Buffer, start: number, end?: number): Buffer {
  * Check if buffer contains printable ASCII
  */
 export function isPrintableAscii(buffer: Buffer, length?: number): boolean {
-  const checkLength = length || buffer.length;
-  
-  for (let i = 0; i < checkLength && i < buffer.length; i++) {
-    const byte = buffer[i];
-    // Check if byte is printable ASCII (0x20-0x7E) or tab/newline/carriage return
-    if (byte < 0x20 || byte > 0x7E) {
-      if (byte !== 0x09 && byte !== 0x0A && byte !== 0x0D) {
-        return false;
-      }
-    }
-  }
-  
-  return true;
+  // Delegate to protocol parser
+  return HttpParser.isPrintableAscii(buffer, length);
 }