[MM-38216] Add API endpoint and adapt search to allow multi-team search (#18371)

* Add API endpoint and adapt search to allow multi-team search

* Refactor handler, refactor sql query to use squirrel, rename app and store functions and add tests

* Fix lint

* Fix search engines and remove unneeded comments

* Fix test

* Remove user from channel after test

store/searchlayer/post_layer.go

@@ -136,7 +136,7 @@ func (s SearchPostStore) PermanentDeleteByChannel(channelID string) error {
 	return err
 }
 
-func (s SearchPostStore) searchPostsInTeamForUserByEngine(engine searchengine.SearchEngineInterface, paramsList []*model.SearchParams, userId, teamId string, page, perPage int) (*model.PostSearchResults, error) {
+func (s SearchPostStore) searchPostsForUserByEngine(engine searchengine.SearchEngineInterface, paramsList []*model.SearchParams, userId, teamId string, page, perPage int) (*model.PostSearchResults, error) {
 	if err := model.IsSearchParamsListValid(paramsList); err != nil {
 		return nil, err
 	}
@@ -170,10 +170,10 @@ func (s SearchPostStore) searchPostsInTeamForUserByEngine(engine searchengine.Se
 	return model.MakePostSearchResults(postList, matches), nil
 }
 
-func (s SearchPostStore) SearchPostsInTeamForUser(paramsList []*model.SearchParams, userId, teamId string, page, perPage int) (*model.PostSearchResults, error) {
+func (s SearchPostStore) SearchPostsForUser(paramsList []*model.SearchParams, userId, teamId string, page, perPage int) (*model.PostSearchResults, error) {
 	for _, engine := range s.rootStore.searchEngine.GetActiveEngines() {
 		if engine.IsSearchEnabled() {
-			results, err := s.searchPostsInTeamForUserByEngine(engine, paramsList, userId, teamId, page, perPage)
+			results, err := s.searchPostsForUserByEngine(engine, paramsList, userId, teamId, page, perPage)
 			if err != nil {
 				mlog.Warn("Encountered error on SearchPostsInTeamForUser.", mlog.String("search_engine", engine.GetName()), mlog.Err(err))
 				continue
@@ -189,5 +189,5 @@ func (s SearchPostStore) SearchPostsInTeamForUser(paramsList []*model.SearchPara
 	}
 
 	mlog.Debug("Using database search because no other search engine is available")
-	return s.PostStore.SearchPostsInTeamForUser(paramsList, userId, teamId, page, perPage)
+	return s.PostStore.SearchPostsForUser(paramsList, userId, teamId, page, perPage)
 }