client: get by id helpers

[ghost]

Telegram API has some methods like channels.getMessages or users.getUsers which is designed to request object by ID, unlike pagination methods.

It would be nice to add helpers for this methods, also see ETag-like caching. Hash algorithm implemented in https://pkg.go.dev/github.com/gotd/td/telegram/query#Hasher.

[spacemolly]

This would be incredibly useful, one of the trickiest part of making a functional telegram app. If it's too much work, maybe just an example of how to to it correctly?

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.