Limit the number of sources per project, and projects per user
As pointed out by @alr6764, the system can trivially be DOS'd by providing an unlimited number of large sources to process. A way to easily complicate this is by limiting the total number of sources a user can limit (likely using a project count limit and a source/project limit)
Acceptance Criteria:
- For any one user, there is a limit to the total number of sources they can enter without deleting another source
- When a user encounters this limit, they are informed as much, and the UI updates accordingly
Potential future work: An ability to flag a user's account to allow them to bypass this limit