* 🔒 fix: `iconURL` in conversation parsing
- Updated the `buildEndpointOption` middleware to derive `iconURL` from model specs when not provided by the client, improving security by preventing malicious URLs.
- Modified the `parseCompactConvo` function to strip `iconURL` from conversation inputs, ensuring it is only set server-side.
- Added comprehensive tests to validate the stripping of `iconURL` across various endpoint types, enhancing overall input sanitization.
* ✨ feat: Add ESLint rule for unused variables
- Introduced a new ESLint rule to warn about unused variables, allowing for better code quality and maintainability.
- Configured the rule to ignore variables and arguments that start with an underscore, accommodating common coding practices.