[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

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

server/channels/db/migrations/postgres/000110_create_desktop_tokens.down.sql

@@ -0,0 +1 @@
+DROP TABLE IF EXISTS desktoptokens;

server/channels/db/migrations/postgres/000110_create_desktop_tokens.up.sql

@@ -0,0 +1,8 @@
+CREATE TABLE IF NOT EXISTS desktoptokens (
+    desktoptoken VARCHAR(64) NOT NULL,
+    userid VARCHAR(26),
+    createat BIGINT NOT NULL,
+    PRIMARY KEY (desktoptoken)
+);
+
+CREATE INDEX IF NOT EXISTS idx_desktoptokens_createat ON desktoptokens(createat);