Should not allow to schedule two event with the same client at the same time

[nus-pe-bot]

When adding a scheduled appointment, it does not make sense to allow adding of a different appointment to the same person and the exact same date and time. This makes it hard to catch mistakes made when user accidentally enters wrong date/time resulting in overlapping appointments!

Steps to reproduce:

1. Run command "schedule add h/Meeting with Client t/2/14/2024 0930 d/Discuss project details n/John Doe"
2. Run command "schedule add h/Meeting with friend t/2/14/2024 0930 d/Discuss project details n/John Doe"

Expected output : "Error, appointment already exist with this person at this date and time"

Reason for severity : While this does not make the app unusable, it represents potential for huge issues when many appointments are stacked at the same time and date. It does not warn the user from adding mutliple appointments.

Actual output : A new appointment is added successfully.

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_{[original: nus-cs2103-AY2324S2/pe-interim#2454] [original labels: severity.Medium type.FeatureFlaw]}

[Rishit02]

Team's Response

It is possible that the social worker is meeting a group of people. For example, the social worker is meeting a group of elderly at a local Community Center event for a group therapy session (or any other reasons), in this scenario it is imperative that the social worker be able to meet with multiple clients at the same time.

This is a feature that can be added in future iterations of the applications (thus, we have changed to NotInScope).

Moreover, it is unlikely that users will be making mistakes by scheduling appointments on the same time, hence, we suggest reducing the severity to low.

Duplicate status (if any):

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