[MM-20979] Add first implementation of the Bleve search engine (#14562)

* [MM-20979] Add first implementation of the Bleve search engine

* Fix i18n

* Migrate searchengine utils tests

* Fix linter

* Don't add allTermsQ if both termQueries and notTermQueries are empty

* Fix test that should work if user is system admin

* Modify naming according to review comments

* Abstract getIndexDir function

* Extracting bleve engine name as a constant

* Merge both Indexer interfaces into one

* Add worker stopped message

* Allow worker to be started/stopped with config change

* Use constants for index names

* Modify test order

* Fix linter

* Trying to unlock the CI

api4/api.go

@@ -86,6 +86,8 @@ type Routes struct {
 
 	Elasticsearch *mux.Router // 'api/v4/elasticsearch'
 
+	Bleve *mux.Router // 'api/v4/bleve'
+
 	DataRetention *mux.Router // 'api/v4/data_retention'
 
 	Brand *mux.Router // 'api/v4/brand'
@@ -198,6 +200,7 @@ func Init(configservice configservice.ConfigService, globalOptionsFunc app.AppOp
 	api.BaseRoutes.Reactions = api.BaseRoutes.ApiRoot.PathPrefix("/reactions").Subrouter()
 	api.BaseRoutes.Jobs = api.BaseRoutes.ApiRoot.PathPrefix("/jobs").Subrouter()
 	api.BaseRoutes.Elasticsearch = api.BaseRoutes.ApiRoot.PathPrefix("/elasticsearch").Subrouter()
+	api.BaseRoutes.Bleve = api.BaseRoutes.ApiRoot.PathPrefix("/bleve").Subrouter()
 	api.BaseRoutes.DataRetention = api.BaseRoutes.ApiRoot.PathPrefix("/data_retention").Subrouter()
 
 	api.BaseRoutes.Emojis = api.BaseRoutes.ApiRoot.PathPrefix("/emoji").Subrouter()
@@ -232,6 +235,7 @@ func Init(configservice configservice.ConfigService, globalOptionsFunc app.AppOp
 	api.InitCluster()
 	api.InitLdap()
 	api.InitElasticsearch()
+	api.InitBleve()
 	api.InitDataRetention()
 	api.InitBrand()
 	api.InitJob()