`update` Command Fails with Valid Attendee Indexes

[bbryant824]

Bug Report: update Command Fails with Valid Attendee Indexes

Title: update command incorrectly displays "Attendee index out of bounds" error for valid attendee indexes.

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Steps to Reproduce

1. Launch LegacyLink.
2. Ensure there are at least 3 events in the event book and at least 2 contacts in the address book.
3. Enter the following command:
   update -i 3 -n New Year's Party -sd 2025-01-01 -ed 2025-01-02 -a 1 2 -l Marine Parade Road #12-34

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Expected Behavior

• The third event should be updated successfully with the provided details.
• The first two contacts should be added as attendees to the event.

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Actual Behavior

• The command fails with the error message:
  Attendee index out of bounds.

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Severity

severity.Medium

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Type

type.FunctionalityBug

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Why This Is a Problem

• Core Functionality Issue: Users cannot update events with valid attendees, undermining the event management functionality.
• Incorrect Validation Logic: The app misinterprets valid attendee indexes as invalid, restricting normal operations.
• User Frustration: Users are blocked from performing basic tasks, potentially leading to confusion and dissatisfaction.

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Suggestions for Improvement

1. Fix the attendee index validation logic to ensure it correctly checks against the existing contact list.
2. Improve error messages to provide more specific feedback, such as identifying which index is considered out of bounds.
3. Add test cases to verify that valid attendee indexes are accepted by the update command.

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