Fix error with undefined choices in new conversations

[tebayoso]

-Added safe navigation to an object that might be undefined on an empty conversation. -Fixes #201

Purpose

• Prevents an error in new projects where empty choices are returned because of the lack of context history.

Does this introduce a breaking change?

[ ] Yes
[x] No

Pull Request Type

What kind of change does this Pull Request introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[x] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

How to Test

• Get the code

git clone [repo-address]
cd [repo-name]
git checkout [branch-name]
npm install

• Test the code

Spin up a new project
Validate that the console displays no errors

What to Check

Verify that the following are valid

• A new conversation without prior context should have no error when retrieving the choices.

Other Information

[sinedied]

Thank you!