feat(telegram): add support for chat topics

[jon4hz]

This PR adds support for telegram chat topics.

github.com/go-telegram-bot-api/telegram-bot-api doesn't have support for topics despite several open PRs, so I switched it out with a more up-to-date library.

Diun supports sending messages to multiple chats so ChatTopics is a 2d slice, which allows diun to send messages to multiple chats and multiple topics.

I couldn't quite figure out how the environment variables are parsed, so I'm not 100% sure if the parsing of multi dimensional arrays works. I'll test that before I remove the draft status.

This is my first time contributing to diun so please let me know if I overlooked something or if have any other comments so far!

Closes #948 and #1031

[jon4hz]

As it seems github.com/crazy-max/gonfig doesn't support multidimensional arrays and I'm getting an error FTL Cannot load configuration error="failed to decode configuration from file: unsupported simple value type: slice".
So I did a little refactor and chatTopics is now a simple array, allowing you to define only one topic per chatID.

[crazy-max]

Can you rebase with #1135 merged? Also see my review, thanks!

[crazy-max]

I don't think we should use a second array to define topics. That's error prone imo.

I think we could either use a separator in chat ID to define topics like 123456789:25 where 123456789 is the chat ID and 25 an optional topic/thread id.

Also I think a chat ID can have multiple topics right?

If that's the case we could either define comma separated list of topic IDs in chat ID like 123456789:25,12 or keep ChatTopics that would be a map like:

chatTopics:
  123456789:
    - 25
    - 12

I would tend to reuse chatIDs with 123456789:25,12

[jon4hz]

I think we could either use a separator in chat ID to define topics like 123456789:25 where 123456789 is the chat ID and 25 an optional topic/thread id.

Unless I'm misunderstanding something, that would mean we'd have to change the chatID to a string, right? That would be a rather breaking change and I'm not sure if that is the best solution.

I made a draft of using a map for the chat topics in 1915c27. It's working but it has the downside that you have to make the map keys explicitly a string (github.com/crazy-max/gonfig doesn't support int64 as map keys).

Let me know what you think!

[ugorur]

did you stop working on this?

[bytebone]

As it stands now, I guess that feedback from crazy-max is required to go forward with this. I am highly interested in this am able + willing to contribute where necessary, should jon no longer be available.

[jon4hz]

Hey, so unfortunately I don't use diun anymore, so I didn't pursue this PR anymore. The next step here is a design decision, and that's up to @crazy-max.

[bytebone]

Thank you jon for your work so far, allow me to pick it up from your last commit. I'll prepare a rebased fork and make a new PR, and we can continue the work there.

Edit: Created at #1305