beta-4.9: Light 'soft glow' removed.

Improvements

• Removed the 'soft glow' effect when winning by enforcing a minimum light intensity of 3. This change was made to address the visual issue reported by a user. (Reference)
• Updated the appearance of the heart to make it more vibrant red. README has been updated to reflect this change.
• Disabled the sword functionality and texture after winning to improve the game's visual aspect (i.e. some pixels of the sword were not showing as the light was expanding whilst winning)