Merge addSyncTask and addTargetedSyncTask into single method with optional target parameter

[guiyanakuang]

Description

Simplify the TaskBuilder API by merging addSyncTask and addTargetedSyncTask into a single addSyncTask method with an optional targetAppInstanceId parameter. Also reorders fileSize as the second parameter for better readability.

Changes

• Remove addTargetedSyncTask from TaskBuilder interface
• Add optional targetAppInstanceId: String? = null parameter to addSyncTask
• Reorder parameters: id, fileSize, appInstanceId, targetAppInstanceId
• Update all call sites accordingly