feat: Add caching module for YouTube video info (#96)

This pull request introduces a new caching module to optimize the retrieval of YouTube video information. By implementing a local caching mechanism, the system avoids repetitive fetch requests to YouTube servers, resulting in significant performance improvements.

- 4c786e7 - feat: Add `cache` module for YouTube video information
- 36c9510 - feat(cache): Add human-readable format option
- cab59e6 - test(unit): Initial unit tests for cache module
- 1362df6 - refactor(cache): Optimize cache validation and handling logic
- cbed754 - test(unit): Add validation scenarios for invalid caches
- 73be3b6 - fix(cache): Remove unnecessary check for video info object
- 3b7d457 - feat(cache): Add `createdDate` property to cache object
- d704f53 - feat(cache): Add function to delete cache
- c1e500d - test(unit): Add test case for cache deletion
- 3df99f5 - docs(cache): Add new typedef for returned cache
- 53a0466 - refactor(cache): Rename a cache directory option
- 8a30405 - test(unit): Address linting issue `mocha/no-setup-in-describe`
- 780cbaf - test(unit): Add test cases for `deleteCache` function
- de128b9 - test(unit): Add test suites for several error classes

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Signed-off-by: Ryuu Mitsuki <dhefam31@gmail.com>