[Feature] Migrate to use `eslint` flat config

[nebula-aac]

Current Behavior

Sistent relies on using eslint@v8

Desired Behavior

Migrate to Eslint flat config file
Remove any packages that will not be used or has not been used

Implementation

Acceptance Tests

Mockups

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Contributor Guide

• 🎨 Wireframes and designs for Sistent site in Figma (open invite)

[Aditya-PS-05]

@nebula-aac , Is this issue still open? Can you assign this to me?