refactor(parcel): migrate to type-safe Parcel read methods

[joshtrichards]

Summary

Migrates deprecated readSerializable() and readParcelable() calls to their type-safe variants using AndroidX ParcelCompat for backward compatibility with Android 9+.

Addresses lint warnings such as these:

w: file:///home/runner/work/android/android/app/src/main/java/com/nextcloud/client/account/RegisteredUser.kt:33:16 'fun <T : Parcelable!> readParcelable(p0: ClassLoader?): T?' is deprecated. Deprecated in Java.
w: file:///home/runner/work/android/android/app/src/main/java/com/nextcloud/client/account/RegisteredUser.kt:34:16 'fun <T : Parcelable!> readParcelable(p0: ClassLoader?): T?' is deprecated. Deprecated in Java.
w: file:///home/runner/work/android/android/app/src/main/java/com/nextcloud/client/account/RegisteredUser.kt:35:16 'fun <T : Parcelable!> readParcelable(p0: ClassLoader?): T?' is deprecated. Deprecated in Java.
w: file:///home/runner/work/android/android/app/src/main/java/com/nextcloud/client/account/Server.kt:22:16 'fun readSerializable(): Serializable?' is deprecated. Deprecated in Java.
w: file:///home/runner/work/android/android/app/src/main/java/com/nextcloud/client/account/Server.kt:23:16 'fun <T : Parcelable!> readParcelable(p0: ClassLoader?): T?' is deprecated. Deprecated in Java.

Changes

• Add readSerializableCompat extension function to existing ParcableExtensions.kt
• Update Server.kt to use extension functions
• Update Request.kt (DownloadRequest & UploadRequest) to use extension functions
• Update RegisteredUser.kt to use extension functions
• Update OCFile.java to use ParcelCompat directly
• Update ConflictDialogData.kt for consistency with type parameters

Why

• Removes deprecation warnings on Android 13+ (API 33+)
• Maintains backward compatibility with minSdk 28 (Android 9)
• Provides type safety at compile time
• Establishes consistent pattern across the codebase

Testing

• Existing Parcelable tests pass
• Account switching works correctly
• File operations (upload/download) work correctly
• No runtime errors on Android 9-14

🖼️ Screenshots

🏚️ Before	🏡 After
B	A

🏁 Checklist

• Tests written, or not not needed

[github-actions]

Codacy

SpotBugs

Category	Base	New
Bad practice	42	42
Correctness	74	74
Dodgy code	257	257
Experimental	1	1
Internationalization	7	7
Malicious code vulnerability	2	2
Multithreaded correctness	34	34
Performance	44	43
Security	18	18
Total	479	478

[github-actions]

APK file: https://www.kaminsky.me/nc-dev/android-artifacts/16488.apk



To test this change/fix you can simply download above APK file and install and test it in parallel to your existing Nextcloud app.

[github-actions]

blue-Light-Screenshot test failed, but no output was generated. Maybe a preliminary stage failed.