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This was a massive code clean-up (and basically re-write at this point 😅) to use better code style practices and fix some bugs.

• The modal should show up in the middle of the view no matter scroll position.
• Adds a small sentence under the input to explain what a "social address" or "instance" is and uses the term "social address" as a more user-friendly term for main text.
• Now checks if the url entered has an https:// in front of it already, and if not adds it on blur.

Adds greater customization of button and ability to replace the button all together.

Allows for greater customization of the button as well as replacing the button all together.