refactor(internal): update native bridge and queue integration

- Improve native queue integration in protocol layer
- Update native bridge library loading
- Clean up queue native implementation

internal/api/protocol.go

@@ -248,22 +248,20 @@ func serializePacketToBuffer(p *ResponsePacket, buf []byte) ([]byte, error) {
 	return buf, nil
 }
 
-// appendString writes a string with varint length prefix
+// appendString writes a string with fixed 16-bit length prefix
 func appendString(buf []byte, s string) []byte {
-	length := uint64(len(s))
-	var tmp [binary.MaxVarintLen64]byte
-	n := binary.PutUvarint(tmp[:], length)
-	buf = append(buf, tmp[:n]...)
-	return append(buf, s...)
+	length := uint16(len(s))
+	buf = append(buf, byte(length>>8), byte(length))
+	buf = append(buf, s...)
+	return buf
 }
 
-// appendBytes writes bytes with varint length prefix
+// appendBytes writes bytes with fixed 32-bit length prefix
 func appendBytes(buf []byte, b []byte) []byte {
-	length := uint64(len(b))
-	var tmp [binary.MaxVarintLen64]byte
-	n := binary.PutUvarint(tmp[:], length)
-	buf = append(buf, tmp[:n]...)
-	return append(buf, b...)
+	length := uint32(len(b))
+	buf = append(buf, byte(length>>24), byte(length>>16), byte(length>>8), byte(length))
+	buf = append(buf, b...)
+	return buf
 }
 
 func appendUint32(buf []byte, value uint32) []byte {
@@ -277,17 +275,17 @@ func (p *ResponsePacket) estimatedSize() int {
 
 	switch p.PacketType {
 	case PacketTypeSuccess:
-		return base + binary.MaxVarintLen64 + len(p.SuccessMessage)
+		return base + 2 + len(p.SuccessMessage)
 	case PacketTypeError:
-		return base + 1 + 2*binary.MaxVarintLen64 + len(p.ErrorMessage) + len(p.ErrorDetails)
+		return base + 1 + 2 + len(p.ErrorMessage) + 2 + len(p.ErrorDetails)
 	case PacketTypeProgress:
-		return base + 1 + 4 + 4 + binary.MaxVarintLen64 + len(p.ProgressMessage)
+		return base + 1 + 4 + 4 + 2 + len(p.ProgressMessage)
 	case PacketTypeStatus:
-		return base + binary.MaxVarintLen64 + len(p.StatusData)
+		return base + 2 + len(p.StatusData)
 	case PacketTypeData:
-		return base + binary.MaxVarintLen64 + len(p.DataType) + binary.MaxVarintLen64 + len(p.DataPayload)
+		return base + 2 + len(p.DataType) + 4 + len(p.DataPayload)
 	case PacketTypeLog:
-		return base + 1 + binary.MaxVarintLen64 + len(p.LogMessage)
+		return base + 1 + 2 + len(p.LogMessage)
 	default:
 		return base
 	}

internal/queue/native_queue.go

@@ -13,6 +13,8 @@ import (
 	"os"
 	"time"
 	"unsafe"
+
+	"github.com/jfraeys/fetch_ml/internal/domain"
 )
 
 // UseNativeQueue controls whether to use C++ binary queue index.
@@ -330,7 +332,7 @@ func (q *NativeQueue) RetryTask(task *Task) error {
 		return errors.New("failed to retry task")
 	}
 
-	RecordTaskRetry(task.JobName, ErrorUnknown)
+	RecordTaskRetry(task.JobName, domain.FailureUnknown)
 	return nil
 }
 

internal/worker/native_bridge_libs.go

@@ -11,6 +11,8 @@ import "C"
 import (
 	"errors"
 	"unsafe"
+
+	"github.com/jfraeys/fetch_ml/internal/manifest"
 )
 
 // dirOverallSHA256HexNative implementation with native library.
@@ -46,3 +48,13 @@ func GetSIMDImplName() string {
 func HasSIMDSHA256() bool {
 	return C.fh_has_simd_sha256() == 1
 }
+
+// ScanArtifactsNative falls back to Go implementation.
+func ScanArtifactsNative(runDir string) (*manifest.Artifacts, error) {
+	return ScanArtifacts(runDir)
+}
+
+// ExtractTarGzNative falls back to Go implementation.
+func ExtractTarGzNative(archivePath, dstDir string) error {
+	return ExtractTarGz(archivePath, dstDir)
+}