Add a fifth type of tower

New tower, bug fixes, UI adjustments, gamepad controls, button settings, sound effects changed, and wave skip function added.

Added a fifth type of tower and its talents,
Type 5 Class 0: The bullet will cause combustion, triggering burning damage after 5 seconds.
Type 5 Class A: Short cooldown. After upgrading, the bullets will randomly ignite an additional nearby enemy.
Type 5 Class B: The bullets will randomly ignite an additional nearby enemy. Upgrading will increase the number.
Type 5 Class C: long cooldown, long attack range, high attack power, the bullets will randomly ignite five nearby enemies, and the number will increase as you upgrade.

Fix the following bugs
Towers sometimes fail to detect enemies and cause significant lag.
The numb time is unlimited.
SP is 1 less.

Adjust UI
When inspecting a space, conflicting towers will also appear as green radius circles, and conflicting walls will appear as red boxes.
The middle mouse button can move the camera directly to where the mouse is pointing.
The camera moves in a smooth manner instead of moving directly to the target point.
Levels can also be selected with the left mouse button.
Added gamepad controls and menu interface.
Added key settings, but cannot replace the following keys Esc, Enter, PageUp/Down, Alt, Ctrl, Shift, F12, CapsLock, NumLock and START and SELECT of the gamepad.
Adjust road sign model.
Changed the sound effects of the first type of towers.
The sound effects become quieter the further away from the camera.
In the paused state, the start/end point patterns become translucent and become smaller the further away from the lens.

Added wave skip function.
In the first wave after entering the level, there will be no monsters coming out directly, and there will be 90 seconds to build the tower.

Added a fourth type of tower and its talents,
Type 4 Class 0: Bullets ignore walls.
Type 4 Class A: Bullets will randomly bounce and attack nearby enemies. If there are no other targets nearby, they will disappear directly.
Type 4 Class B: The bullet will penetrate the enemy and bounce off the wall until it reaches the upper limit of movement.
Type 4 Class C: The bullet will stay on the enemy, cause damage to the enemy again after one second, then randomly bounce and attack nearby enemies. If there are no other targets nearby, it will disappear directly.

Fixed a bug where clicking on the tower would cause game errors.

Adjusted some bullet models and road sign models.
Changed the sound effects of the first type of towers.
Talent: The upper limit of the ice effect is changed from 0.5 seconds to 1 second.
Talent: WP limit changed from 10 to 20.
WP production time changed from 15 seconds to 30 seconds.
The waiting time for enemy waves has been changed from 10 seconds to 90 seconds.
In addition to the space bar, left-clicking the "enemy icon" at the top of the game can also skip the "enemy wave waiting time".
In the paused state, left-clicking the start/end point icon will move to the start/end point position.