wrapped up adding javaDoc and refactoring NewGuildJoined

[tsanevp]

Changes made:

CommandModule.java:

• Removed lines 21-27 "StringSelectHandler" for NewGuildJoined. No longer using a drop-down menu
• Moved ButtonHandler provideButtonCreateListingClickHandler() to be next to its SlashCommandHandler for CreateListingCommand

CreateListingCommand.java:

• Renamed method name to be .getTradingChannelId since we need the channel ID not the name

NewGuildJoined.java:

• Lines 28-37 are static variables that do not change and take up space in the methods. Need y'alls opinion on if we should keep them at the top or add them back into the code.
• Changes variable types to be "var" per lombok
• Added javadoc explaining what the methods are for and steps along the way in each method
• Removed the menu-drop down ability of the guild owner to be able to assign an existing channel as the trading channel. The bot's trading channel needs to have specific permissions, which is why I decided it would be best to create a fresh new channel, rather than edit and restrict possibly an existing channel that has sensitive content in it. That would be the best approach and most user friendly. The owner can always rename the new channel to whatever they want since we store the ChannelId not name.
• Created new method "sendPrivateMessage" that is used to send a DM to a user. Removed redundancy of privateChannel builder and make the code easier to understand. (this will later be factored out into a parent MessageHelper class that other classes can also utilize)
• createNewTradingChannel method now can be passed any name. Will eventually factor this out into into the class mentioned above. Will need to be able to call this method from NewGuildJoined.java or CreateTradingChannel.java (yet to be created)

User.java/UserController.java:

• Updated to store tradingChannelId not name

[lenad90]

I think if the variable is used more than once, than it's a must. But some variables are hard to understand with just the variable name, and I think it would be easier for readability to have it back in the code just so that it doesn't have to require the reader to refer back to the top class to see what the variable is.

[tsanevp]

This is true, but some of the strings are super long. I don't mind adding them back in, but if you hover over the variable name, it shows the whole string, so you don't need to refer back to the top. If you still think we should add them back in, I am all for it and will update that before I merge.

[lenad90]

@tsanevp Oh I didn't know about the hover! That does make it easier. I'm okay with either, but this stackoverflow thread might help with your decision: https://stackoverflow.com/questions/4234129/should-i-use-constants-instead-of-strings-even-if-the-strings-are-only-ever-used

[tsanevp]

Okay, based on that and your input, I'll only factor out the strings that occur more than once. Otherwise I agree that it might make it hard to understand the string being sent.