Improve login flow

[alperozturk96]

Changes

• Handles restore pending login flow and cancel better
• Uses kotlinx.serialization instead of Gson
• Adds more logs to clearly follow execution flow in the logs

[codecov]

Codecov Report

❌ Patch coverage is 3.19149% with 91 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
.../android/authentication/AuthenticatorActivity.java	3.37%	82 Missing and 4 partials ⚠️
.../com/owncloud/android/authentication/AuthObject.kt	0.00%	5 Missing ⚠️

📢 Thoughts on this report? Let us know!

[github-actions]

📱 QA build

Download	app-qa-debug.apk
QR code	Open the QR code for this download
Commit	0650bf6
Version	17824
Available until	7 days after this build

The QA build installs alongside a released Nextcloud app, so you can keep
using your existing install while testing.

Downloading the file requires a GitHub account, so open this link on the
device you want to test on, or transfer the APK to it.

[github-actions]

Codacy

SpotBugs

Category	Base	New
Bad practice	25	25
Correctness	52	52
Dodgy code	161	161
Experimental	1	1
Malicious code vulnerability	1	1
Multithreaded correctness	20	20
Performance	28	28
Security	16	16
Total	304	304