Added health bar and snail behavior enhancements

- Introduced a health bar for flowers, which updates based on the current GameState values.
- Enhanced snail behavior with eating and sleeping states. Snails now have a chance to switch to the sleeping state while eating.
- Improved mouse interaction with snails, allowing them to potentially switch to sleep mode when clicked.
- Refactored cursor management into its own class for better code organization and readability.
- Updated drone placement logic to use the new CursorManager class.
- Added functionality for bees to replenish flower nectar levels after a certain number of deposits.

levels/level_2.tscn

@@ -144,6 +144,7 @@ unique_name_in_owner = true
 z_index = 900
 offset_right = 1280.0
 offset_bottom = 720.0
+mouse_filter = 1
 
 [node name="DroneManager" parent="." instance=ExtResource("13_pibpn")]
 unique_name_in_owner = true