use app identifier instead of ctx

changing this because ctx is commonly used with the context package.

setup.go

@@ -10,14 +10,14 @@ type testReq struct {
 	Password string `json:"jfPassword"`
 }
 
-func (ctx *appContext) TestJF(gc *gin.Context) {
+func (app *appContext) TestJF(gc *gin.Context) {
 	var req testReq
 	gc.BindJSON(&req)
 	tempjf := Jellyfin{}
-	tempjf.init(req.Host, "jfa-go-setup", ctx.version, "auth", "auth")
+	tempjf.init(req.Host, "jfa-go-setup", app.version, "auth", "auth")
 	_, status, err := tempjf.authenticate(req.Username, req.Password)
 	if !(status == 200 || status == 204) || err != nil {
-		ctx.info.Printf("Auth failed with code %d (%s)", status, err)
+		app.info.Printf("Auth failed with code %d (%s)", status, err)
 		gc.JSON(401, map[string]bool{"success": false})
 		return
 	}