Many QoL Enhancements & Tweaks

It's taken me seven months but I have finally gotten around to updating the game with many of the suggestions and feedback that I got from all the people that played the game after the game jam ended. Here's what's new and changed in this update:

• Implemented auto fire by holding down the attack button (or space bar)
• Ship has a higher mass and will knock small asteroids out of the way
• New shield indicator around the ship - will flash red when hit
• Shield alerts at 75%, 50%, 25% and 10%
• Scoring replaced by a mission timer for each planet
• If you don't protect the planet before the timer runs out, the planet explodes!
• Prevent ship from being damaged or bumped by asteroids during shield deployment
• Initiating the credits sequence will remove the credits button
• Implemented a better ending for mission completion

A lot of people asked for a more comprehensive game featuring things like ship upgrades and that would be cool to do, but it would really need to be a different kind of game for that, and maybe one day I will make Asterworlds 2 which could have resource mining, a better mission structure and upgradeable ships 😊

I'd very much appreciate your feedback! If you play after this update please let me know how it feels to play now.