Populate minigame with obstacles and monster spawns (#5)

- Simulated "fake" physics and collisions
- Object pooling for tiles, obstacles and monster spawns
- Base monster scoring with proximity triggers and depth multiplier

Co-authored-by: AlexanderT <alexander@foolhardyhorizons.com>
Co-authored-by: Michal Pikulski <michal.a.pikulski@gmail.com>
Reviewed-on: #5

.gitignore

@@ -99,6 +99,8 @@ InitTestScene*.unity*
 
 # Auto-generated scenes by play mode tests
 /[Aa]ssets/[Ii]nit[Tt]est[Ss]cene*.unity*
+.idea/.idea.AppleHillsProduction/.idea/indexLayout.xml
 .vscode/extensions.json
 .vscode/launch.json
 .vscode/settings.json
+.idea/.idea.AppleHillsProduction/.idea/indexLayout.xml