目录重构完成，但是Preview通道尚未可用

internal/process/lock_linux.go

@@ -0,0 +1,67 @@
+//go:build linux
+
+package process
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"time"
+
+	"golang.org/x/sys/unix"
+)
+
+// Lock 获取进程间互斥锁 (Linux: flock)
+func (pm *ProcessManager) Lock() error {
+	pm.mu.Lock()
+	defer pm.mu.Unlock()
+
+	if pm.locked {
+		return nil
+	}
+
+	lockPath := filepath.Join(pm.dataDir, LockFileName)
+	if err := os.MkdirAll(pm.dataDir, 0755); err != nil {
+		return fmt.Errorf("创建数据目录失败: %w", err)
+	}
+	file, err := os.OpenFile(lockPath, os.O_CREATE|os.O_RDWR, 0644)
+	if err != nil {
+		return fmt.Errorf("打开锁文件失败: %w", err)
+	}
+
+	start := time.Now()
+	for {
+		err := unix.Flock(int(file.Fd()), unix.LOCK_EX|unix.LOCK_NB)
+		if err == nil {
+			pm.lockFile = file
+			pm.locked = true
+			return nil
+		}
+		if err != unix.EWOULDBLOCK {
+			file.Close()
+			return fmt.Errorf("获取锁失败: %w", err)
+		}
+		if time.Since(start) > LockAcquireTimeout {
+			file.Close()
+			return fmt.Errorf("获取锁超时 (超过 %v)", LockAcquireTimeout)
+		}
+		time.Sleep(LockRetryInterval)
+	}
+}
+
+// Unlock 释放互斥锁 (Linux: flock)
+func (pm *ProcessManager) Unlock() error {
+	pm.mu.Lock()
+	defer pm.mu.Unlock()
+
+	if !pm.locked {
+		return nil
+	}
+	if pm.lockFile != nil {
+		unix.Flock(int(pm.lockFile.Fd()), unix.LOCK_UN)
+		pm.lockFile.Close()
+		pm.lockFile = nil
+	}
+	pm.locked = false
+	return nil
+}