feat: cache support

[ANDREY0214]

adds support for caching

based on #47 PR but since there no activity will try propose solution also related to #30

• [x] switched storage to "unstorage" with default driver
• [x] removed fs direct calls
• [x] switched hash lib to "ohash" (just in case same package scope from unjs)
• [x] tests ready for cache option
• [ ] docs updated

example test with: f_webp&q_70&s_1000x1000/https://images.pexels.com/photos/674010/pexels-photo-674010.jpeg

let me know if i something missed really need this feature released :)

[ANDREY0214]

@pi0 Hi, take a look when u have time

[pi0]

Hi dear @ANDREY0214 thanks so much for working on this PR and sorry took long so far. ❤️

Based on new storage implementation in ipx v2, i plan to work on this feature. We can track it via #30.

Closing this PR for maintenance.