feat: support general users view and cancel own tasks (#7416 close #7398)

* feat: support general users view and cancel own tasks

Add a creator attribute to the upload, copy and offline download
tasks, so that a GENERAL task creator can view and cancel them.

BREAKING CHANGE:

1. A new internal package `task` including the struct `TaskWithCreator`
   which embeds `tache.Base` is created, and the past dependence on
   `tache.Task` will all be transferred to dependence on this package.
2. The API `/admin/task` can now also be accessed via `/task`, and the
   old endpoint is retained to ensure compatibility with legacy
   automation scripts.

Closes #7398

* fix(deps): update github.com/xhofe/tache to v0.1.3

server/middlewares/auth.go

@@ -127,6 +127,16 @@ func Authn(c *gin.Context) {
 	c.Next()
 }
 
+func AuthNotGuest(c *gin.Context) {
+	user := c.MustGet("user").(*model.User)
+	if user.IsGuest() {
+		common.ErrorStrResp(c, "You are a guest", 403)
+		c.Abort()
+	} else {
+		c.Next()
+	}
+}
+
 func AuthAdmin(c *gin.Context) {
 	user := c.MustGet("user").(*model.User)
 	if !user.IsAdmin() {