feat: multiple search indexes (#2514)

* refactor: abstract search interface

* wip: ~

* fix cycle import

* objs update hook

* wip: ~

* Delete search/none

* auto update index while cache changed

* db searcher

TODO: bleve init issue

cannot open index, metadata missing

* fix size type

why float64??

* fix typo

* fix nil pointer using

* api adapt ui

* bleve: fix clear & change struct

internal/search/progress.go

@@ -0,0 +1,36 @@
+package search
+
+import (
+	"context"
+
+	"github.com/alist-org/alist/v3/internal/conf"
+	"github.com/alist-org/alist/v3/internal/db"
+	"github.com/alist-org/alist/v3/internal/model"
+	"github.com/alist-org/alist/v3/internal/setting"
+	"github.com/alist-org/alist/v3/pkg/utils"
+	log "github.com/sirupsen/logrus"
+)
+
+func Progress(ctx context.Context) (*model.IndexProgress, error) {
+	p := setting.GetStr(conf.IndexProgress)
+	var progress model.IndexProgress
+	err := utils.Json.UnmarshalFromString(p, &progress)
+	return &progress, err
+}
+
+func WriteProgress(progress *model.IndexProgress) {
+	p, err := utils.Json.MarshalToString(progress)
+	if err != nil {
+		log.Errorf("marshal progress error: %+v", err)
+	}
+	err = db.SaveSettingItem(model.SettingItem{
+		Key:   conf.IndexProgress,
+		Value: p,
+		Type:  conf.TypeText,
+		Group: model.SINGLE,
+		Flag:  model.PRIVATE,
+	})
+	if err != nil {
+		log.Errorf("save progress error: %+v", err)
+	}
+}