Add autocompletion for FossaBot & StreamElements commands

[jupjohn]

Describe your issue

Remembering commands of bots can be very tedious.

A possible solution would be to allow auto completing commands from an external sources in the input.

StreamElements API endpoints:

• https://api.streamelements.com/kappa/v2/channels/<channel_login>
  • Provides SE-specific info for the given channel (username, not channel ID)
• https://api.streamelements.com/kappa/v2/bot/commands/<se_channel_id>/default
  • Provides the list of default commands SE offers for this channel
  • <se_channel_id> is an ID generated by StreamElements and is available in the previous call's _id property
• https://api.streamelements.com/kappa/v2/bot/commands/<se_channel_id>/channel
  • Provides a list of channel-specific commands

Fossabot API endpoints:

• https://api-v1.fossabot.com/api/v1/<channel_login>/public-commands
  • Provides all commands for the specified channel name

fourtf: edited to fit issue template

[fourtf]

From the issue it isn't immediately clear what issue this solves . "QOL" doesn't cut it. Please edit this issue with the issue template and rephrase it as an issue (e.g., remembering commands of bots is very tedious).

For the actual problem I could see there being a Chatterino controlled API that allows people to add their bots to the list. Manually calling 50 apis for every big and tiny bot is infeasible.

[fourtf]

As @pajlada Discord seems to handle commands by bots similarly, where they show the bots commands when typing a command with /

[jupjohn]

Didn't use a template as the feature template has disappeared :\ If you want it done in an issue template I can do.
Will rewrite, words didn't come out in a logical order :)

Cheers 4tf

[fourtf]

updated to fit the template

[jupjohn]

@fourtf any further thoughts on this or are you saving it for a rainy day?

[fourtf]

I'll take a look at it today