Refactor birthday, olympia, space, and sports animations; enhance symbol management and visual effects

- Updated birthday.js to improve balloon visuals and confetti effects, including new color schemes and enhanced pop animations.
- Removed legacy fallback logic in olympia.js and improved image error handling.
- Enhanced space.js with configurable counts for planets, astronauts, satellites, ISS, and rockets; improved shooting star animations and added random image swapping.
- Simplified sports.js by removing legacy emoji fallback logic and optimizing ball creation based on selected categories.
- Adjusted CSS styles across birthday, olympia, space, and sports for better visual consistency and performance.
[skip ci]

Jellyfin.Plugin.Seasonals/Web/olympia.css

@@ -13,7 +13,6 @@
 .olympia-symbol {
     position: absolute;
     top: -10vh;
-    font-size: 3rem;
     opacity: 0.95;
     text-shadow: 0 0 10px rgba(255,255,255,0.2);
     z-index: 40;
@@ -48,7 +47,6 @@
 .olympia-symbol {
     position: absolute;
     top: -10vh;
-    font-size: 4rem;
     opacity: 0.95;
     text-shadow: 0 0 10px rgba(255,255,255,0.2);
     z-index: 40;