feat: add connection config file support

[justinlettau]

Description

Add support for storing connections in a separate config file. Closes #28

Checklist

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• Tests for any changes have been added (for bug fixes / features).
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Type

What kind of change does this pull request introduce?

[ ] Bug.
[x] Feature.
[ ] Code style update (formatting, local variables).
[ ] Refactoring (no functional changes, no api changes).
[ ] Build related changes.
[ ] CI related changes.
[ ] Documentation content changes.
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Breaking Changes

Does this pull request introduce any breaking changes?

[ ] Yes
[x] No

Other Information

n/a