Fixed several bugs in StartHere.kt, including:

• A bug where the backend would return a 500 when signing in despite authenticating successfully.
• A bug where the app would crash after making an account, due to a redundant API call.
• Bugs where the app would crash when any exception was thrown (due to issues with supportFragmentManager).
• Visual bug on the tap words screen where tapping on a wrong word would cause the whole screen to move around.
• Sped up animations to strike balance between prettiness and functionality.
• Modified progress icon sizes to make them more consistent.
• Simplified code in StartHere.kt and NetworkUtilities.kt.