Add fallback split levels and permanent split visibility

Hey! This is my first ever PR on an open source repo, so excuse me if the formatting is a bit off or if I missed something obvious lol. I really like the addon and play a ton of M+, and since I was getting pretty bored in my college lecture today, I decided to fork it and add a couple of split features that I felt were missing: ### 1. Always show splits toggle I added a simple option so we can keep the personal best splits visible on screen even after the key actually starts. I found it a bit annoying to try and memorize my target times once the run began. ### 2. Fallback levels Right now if I run a +15 and I don't have a record for it yet, the splits are just blank. So I added a dropdown to pick a "fallback" level from the database to use as a reference. I added 4 choices: - _highest_ : just grabs your highest key - _lowest_ : grabs your lowest key - _closest_higher_ : grabs the closest key above your current one - _closest_lower_ : grabs the closest key right below it (If you pick _closest_higher_ and don't actually have a higher key recorded, it just falls back to the lower one so it doesn't break). I have tested it for a few days now and it seems to work fine (at least for me :D), i'll continue testing it since i did it for myself xD I've attached a screenshot of how the general options tab looks now, also the looks of it ingame. For example this one is _Academy_ in +12 but i only have the data for a +20, i set the settings to the closest higher : <img width="906" height="401" alt="image" src="https://github.com/user-attachments/assets/82af59cd-7906-4635-a95d-f3ff9594baba" /> This is for the closest but lower this time : <img width="763" height="377" alt="image" src="https://github.com/user-attachments/assets/ec112d23-c063-484e-91cd-b1dc16d3180b" /> Lowest : <img width="700" height="397" alt="image" src="https://github.com/user-attachments/assets/2cd924f2-5fca-489b-a8b8-abb134b08e1e" /> Highest : <img width="723" height="373" alt="image" src="https://github.com/user-attachments/assets/e54cdd74-4736-4e91-bac0-b59c041d58d3" /> None : <img width="719" height="381" alt="image" src="https://github.com/user-attachments/assets/5ff2acae-53a5-41c5-a2de-d2826ea3c095" /> New settings : <img width="1096" height="229" alt="image" src="https://github.com/user-attachments/assets/011fe246-104b-4189-9e9b-85adf745b3b5" /> <img width="508" height="427" alt="image" src="https://github.com/user-attachments/assets/6795dcbc-0bb3-4b68-8be9-9efb4f7bfdbb" /> Let me know if I need to change the code or if you want me to do anything differently!