feat(trin-storage): add filter to store

[njgheorghita]

What was wrong?

Soon, we'll need the ability to remove certain content from our storage according to a specified "validation function". This pr implements the ability to filter such data from the storage.

How was it fixed?

Added filter feature to storage

To-Do

• Clean up commit history and use conventional commits.

[morph-dev]

Regardless if we decide to postpone this for later, I would like to highlight an issues with this approach.

Pagination doesn't really guarantee that you will see all entries. Consider following scenarios:

Scenario 1: Entries changing pages

1. Query first page (entries 1-100) and delete 10 of them because they didn't pass the filter
2. Query second page (entries 101-200)

Result: Entries that were originally at index 101-110 were never queried (because at the moment of second query they were moved to 91-100).

This can be avoided by either:

• tracking number of deletes and updating offset
• saving all entry keys to delete, and delete them once we finished iterating entire db

Scenario 2: Running as a separate task while trin normal operation are running as well

If trin is running normally, we can't avoid issue from Scenario 1 because trin can delete entries (e.g. using pruning) and affect pagination in a way that we can't control.

Note: This can be avoid by simply only running filtering on startup, but that should be documented (if not enforced).