perf: multi-thread downloader, Content-Disposition (#4921)

general: enhance multi-thread downloader with cancelable context, immediately stop all stream processes when canceled;
feat(crypt): improve stream closing;
general: fix the bug of downloading files becomes previewing stream on modern browsers;

Co-authored-by: Sean He <866155+seanhe26@users.noreply.github.com>
Co-authored-by: Andy Hsu <i@nn.ci>

drivers/base/util.go

@@ -1,19 +1 @@
 package base
-
-import "io"
-
-type Closers struct {
-	closers []io.Closer
-}
-
-func (c *Closers) Close() (err error) {
-	for _, closer := range c.closers {
-		if closer != nil {
-			_ = closer.Close()
-		}
-	}
-	return nil
-}
-func (c *Closers) Add(closer io.Closer) {
-	c.closers = append(c.closers, closer)
-}