Parse Live query doesn't work and fails in the decoding because it doesn't have pointer key.

[aliasad106]

New Issue Checklist

• [ x] I am not disclosing a vulnerability.
• [ x] I am not just asking a question.
• [ x] I have searched through existing issues.
• [x ] I can reproduce the issue with the latest versions of Parse Server and the Parse ObjC SDK.

Issue Description: Parse Live Query Fails Due to Missing Pointer Key

Summary:
Parse Live Query encounters a failure during decoding because the expected pointer key is missing. This prevents the Live Query feature from functioning as intended.

Steps to Reproduce:

1. Configure Parse Server with Live Query enabled.
2. Set up a class that includes a pointer field.
3. Subscribe to Live Query for the specified class.
4. Perform a create/update/delete operation on the class that involves the pointer field.

Expected Behavior:
Live Query should handle and decode the operation successfully, including resolving the pointer field.

Actual Behavior:
The Live Query decoding process fails due to the absence of the pointer key, causing the subscription to break or miss updates.

Environment:

• Parse Server version: [e.g., 6.x.x]
• Client SDK version: [e.g., JavaScript/iOS/Android SDK version]
• Database: [e.g., MongoDB/Postgres]
• Node.js version: [e.g., 16.x.x]

Logs and Error Messages:
Provide any relevant logs or error messages from the Parse Server or client console. For example:

Error: Live Query decoding failed: Missing key for pointer field "Pointer".

Possible Cause:
The server or client-side implementation may not properly serialize or include the pointer key during Live Query updates.

Proposed Solution:
Ensure that the pointer key is included in the Live Query payload during serialization or decoding. This could involve:

1. Updating the Parse Server to always include the pointer key for relevant fields.
2. Fixing client SDK handling to process partial data without breaking.

Additional Context:
Include any other relevant details, such as custom configurations or similar issues reported by other users.

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This description provides a clear explanation of the issue, making it easy for maintainers or contributors to understand and address the problem.

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[themoonlitknight]

Do you have afterLiveQueryEvent implemented on your server? I noticed I have this issue in that case so I added a fix on my fork in ClientPrivate.swift.

private func parseObject<T: PFObject>(_ objectDictionary: [String:AnyObject]) throws -> T {
    guard let _ = objectDictionary["className"] as? String else {
        throw LiveQueryErrors.InvalidJSONError(json: objectDictionary, expectedKey: "parseClassName")
    }
    guard let _ = objectDictionary["objectId"] as? String else {
        throw LiveQueryErrors.InvalidJSONError(json: objectDictionary, expectedKey: "objectId")
    }
    
    // *** workaround to fix parsing when afterLiveQueryEvent is active on server
    let fixedObjectDictionary: [String: AnyObject]
    if objectDictionary["__type"] == nil {
        var tmp = objectDictionary
        tmp["__type"] = "Object" as AnyObject
        fixedObjectDictionary = tmp
    } else {
        fixedObjectDictionary = objectDictionary
    }

    guard let object = PFDecoder.object().decode(fixedObjectDictionary) as? T else {
        throw LiveQueryErrors.InvalidJSONObject(json: objectDictionary, details: "cannot decode json into \(T.self)")
    }

    return object
}