Redesign caching

Problem
The caching of rate is not consistent (writing, retrieving and invalidation).
Especially when vote results are recalculated or votes are retrieved, there are several inefficiencies.

Solution
Redesign the logic and streamline cache usage in rate 8.x-2.x.

Tasks

• Define caching and cache invalidation logic (items, tags)
• Modify vote retrieval
• Modify vote results and vote option results retrieval
• Modify vote saving (result recalculation and cache storage)