Implement UpgradeManager and Add Gem Reward for Game Completion

[suhynnoh]

Additions

FileManager.java

• Added methods for reading and writing upgrade_status.properties file:
  • loadUpgradeStatus
  • saveUpgradeStatus
  • loadDefaultUpgradeStatus

UpgradeManager

• Added a class to manage player stat upgrades:
  • Coin acquisition multiplier
  • Ship movement speed
  • Bullet speed
  • Bullet firing speed

TitleScreen

• Implemented Merchant functionality:
  • Upgrades are now properly applied to the player's stats.

ScoreScreen.java

• Added functionality to reward 1 gem to the player when they clear the game.
  • Gems are given every time a player completes the game without dying at the final level.

Modifications

PlayerGrowth

• PlayerGrowth, which contains the basic information of the Ship object, is now initialized using values from upgrade_status.properties.

RoundState

• Stat bonuses are now initialized using values from upgrade_status.properties.

ScoreScreen.java

• Added saveGem() to increase the gem count by 1 upon game completion.
• Implemented conditions to display the game clear screen and trigger saveGem() only when the game is cleared.

DrawManager.java

• Added drawGameClear() to render the game clear screen.

Miscellaneous

This PR focuses on implementing features in collaboration with the Item and Main Menu teams. Please note that gem consumption and upgrade level settings will be handled through future collaboration.

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Visual Examples