[MM-37984] Allow Desktop App to authenticate via external providers outside of the app on supported servers (#23795)

* WIP

* Add rate limiting for desktop token API

* Missing mocks

* Style fixes

* Update snapshots

* Maybe use an actual redirect link :P

* Refactoring for tests

* Add tests for server

* Fix lint issue

* Fix tests

* Fix lint

* Add front-end screen component

* Component logic

* Style changes

* Quick style fix

* Lint fixes

* Initial PR feedback

* Enable logging into the browser as well when completing the login process

* Refactor to push more logic to the other component

* Remove unnecessary helper code

* Fix i18n

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

server/channels/jobs/cleanup_desktop_tokens/scheduler.go

@@ -0,0 +1,20 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package cleanup_desktop_tokens
+
+import (
+	"time"
+
+	"github.com/mattermost/mattermost/server/public/model"
+	"github.com/mattermost/mattermost/server/v8/channels/jobs"
+)
+
+const schedFreq = 1 * time.Hour
+
+func MakeScheduler(jobServer *jobs.JobServer) model.Scheduler {
+	isEnabled := func(cfg *model.Config) bool {
+		return true
+	}
+	return jobs.NewPeriodicScheduler(jobServer, model.JobTypeCleanupDesktopTokens, schedFreq, isEnabled)
+}

server/channels/jobs/cleanup_desktop_tokens/worker.go

@@ -0,0 +1,36 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package cleanup_desktop_tokens
+
+import (
+	"time"
+
+	"github.com/mattermost/mattermost/server/public/model"
+	"github.com/mattermost/mattermost/server/v8/channels/jobs"
+	"github.com/mattermost/mattermost/server/v8/channels/store"
+	"github.com/mattermost/mattermost/server/v8/platform/services/configservice"
+)
+
+const jobName = "CleanupDesktopTokens"
+const maxAge = 5 * time.Minute
+
+type AppIface interface {
+	configservice.ConfigService
+	ListDirectory(path string) ([]string, *model.AppError)
+	FileModTime(path string) (time.Time, *model.AppError)
+	RemoveFile(path string) *model.AppError
+}
+
+func MakeWorker(jobServer *jobs.JobServer, store store.Store) model.Worker {
+	isEnabled := func(cfg *model.Config) bool {
+		return true
+	}
+	execute := func(job *model.Job) error {
+		defer jobServer.HandleJobPanic(job)
+
+		return store.DesktopTokens().DeleteOlderThan(time.Now().Add(-maxAge).Unix())
+	}
+	worker := jobs.NewSimpleWorker(jobName, jobServer, execute, isEnabled)
+	return worker
+}