[WIP][Welcome] Add dynamic welcome image generation

[jlacsamana]

Summary

Implements the features requested in Issue #579 as requested.

Testing

Loading Cog

Creating Directory To Store Images (Has folders for each server)
Before

After

Ensure Directory To Store Images For Specific Server exists: ensureCurrentServerHasImgCache()
Before

After

Random Welcome Image Generation: generateRandWelcomeImg()

3 Passes of the the random image generator

Welcome Image toggle on and off: [p]welcomeset greetings toggleimg
When there is no cache created for this server, make one & toggle to false

If there are no images in cache, toggle to false, and alert user about it

If there are images in cache, and currently toggled false, toggle true

If there are images in cache, and currently toggled true, toggle false

Fetch Image Template: [p]welcomeset greetings image template

Add a new image: [p]welcomeset greetings image add
if an image is added with an unused name

if image is added, but name is already in use

if command is used, but no image is provided

if command is used, but multiple images are provided

Remove an existing image by name: [p]welcomeset greetings image remove
if name specified matches the name of an image in this server's cache

if name specified doesn't match the name of any image in this server's cache

if last image removed, toggles off random image generation

View an image, fetched from server's image cache by name: [p]welcomeset greetings image view
if name specified matches the name of an image in this server's cache

if name specified doesn't match the name of any image in this server's cache

Fetch the list of all the names of the images in this server's welcome image cache: [p]welcomeset greetings image list
If there are no images in the cache yet

When there are images in the cache

[quachtridat]

Could you exclude other files and only include cogs/welcome files in the PR? Let the changes be local to the issue you're fixing 👍

[abelathomas]

Hola, do we have any updates on this @jlacsamana ?
Also please note that this is out of date due to the dpy2 update

[Injabie3]

Did a first pass on latest changes, please add screenshots of the testing done.

[quachtridat]

Noted a number of things. Also can you add type hints for your methods too? I see that command handling methods have type hints but not the rest.
There are a number of .vs files so please exclude them.

[Injabie3]

Any updates on this one?

[quachtridat]

Did a quick pass. A few TODOs for you:

• Resolve all the comments. There are still unresolved comments from past reviews without any replies.
• Keep sentences in docstring and replies consistent. Some of them have multiple verb tenses and don't end with a dot or an exclamation mark.
• Exclude irrelevant files. I see unnecessary .gitignore and .vs changes that get committed, but they don't contribute to the feature you're implementing. If you need to have your own .gitignore, you can add your own one with Git global setting core.excludesFile. Try to prepare your PR properly so that only files in cogs/welcome are included.

[quachtridat]

Also I've got to break it to you...
I don't see the use of emojis helps with your commits. If your commits have to do with black reformatting, grammar fixes, etc., then please describe them accordingly, and vice versa, also try to keep your changes true to what is described by their respective commits. Even though PR commits get squashed before merging, commit messages are still important in explaining changes along the way.

[Injabie3]

Please remove all VS code additions from this PR.