feat(fix): Fix prettier organize imports, lint.

[rossbulat]

Updates the project's prettier config to accommodate version 3:

• Re-activates prettier-plugin-organize-imports by adding it to the prettier config.
• Moves prettier config to package.json under the prettier key.
• Tidies up .prettierignore with better categorization, and removes tsconfig.json files.
• Project-wide lint

Misc:

• Removes outdated eslint-plugin-prefer-arrow eslint plugin.