feat: add permissions attr to channels

[AstreaTSS]

Pull Request Type

• Feature addition
• Bugfix
• Documentation update
• Code refactor
• Tests improvement
• CI/CD pipeline enhancement
• Other: [Replace with a description]

Description

In the Discord API docs for channels, I noticed an attribute called permissions, which gives the calculated permissions for the current bot user if the channel was gotten as an option from a slash command. This PR adds that attribute into interactions.py itself.

Note: technically, Discord doesn't specify that it'll not exist in DMs, but... yeah, it doesn't exist in DMs. I've decided to keep it in BaseChannel regardless to be consistent with Discord though.

Changes

• Add permissions to BaseChannel.

Related Issues

Test Scenarios

@interactions.slash_command(name="cmd", description="My command")
@interactions.slash_option(
    name="chan",
    description="My channel option",
    opt_type=interactions.OptionType.CHANNEL,
    required=True,
)
async def cmd(ctx: interactions.SlashContext, chan: interactions.BaseChannel):
    await ctx.send(str(chan.permissions))

Python Compatibility

• I've ensured my code works on Python 3.10.x
• I've ensured my code works on Python 3.11.x

Checklist

• I've run the pre-commit code linter over all edited files
• I've tested my changes on supported Python versions
• I've added tests for my code, if applicable
• I've updated / added documentation, where applicable