modulo conversion for 515 (#6264)

# About the pull request


![image](https://github.com/cmss13-devs/cmss13/assets/14267245/f04d12d5-ce42-493b-814a-a22a2e56fbd2)
https://www.byond.com/docs/ref/#/operator/%25%25

With the move to 515, removes this define in favor of `x %% y`:
`#define MODULUS(x, y) ( (x) - (y) * round((x) / (y)) )`
And this one in favor of `x %% 360`:
`#define SIMPLIFY_DEGREES(degrees) (MODULUS((degrees), 360))`

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# Explain why it's good for the game

Less bespoke code means less points of failure.
# Testing Photographs and Procedure
Boots without obvious issue.


# Changelog
No player-facing changes.

code/__DEFINES/_math.dm

@@ -19,19 +19,12 @@
 // round() acts like floor(x, 1) by default but can't handle other values
 #define FLOOR(x, y) ( floor((x) / (y)) * (y) )
 
-// Real modulus that handles decimals
-#define MODULUS(x, y) ( (x) - (y) * round((x) / (y)) )
-
 // Returns true if val is from min to max, inclusive.
 #define ISINRANGE(val, min, max) ((min) <= (val) && (val) <= (max))
 
 // Same as above, exclusive.
 #define ISINRANGE_EX(val, min, max) ((min) < (val) && (val) < (max))
 
-// Will filter out extra rotations and negative rotations
-// E.g: 540 becomes 180. -180 becomes 180.
-#define SIMPLIFY_DEGREES(degrees) (MODULUS((degrees), 360))
-
 /// Gets the sign of x, returns -1 if negative, 0 if 0, 1 if positive
 #define SIGN(x) ( ((x) > 0) - ((x) < 0) )
 

code/__HELPERS/_time.dm

@@ -92,21 +92,21 @@ GLOBAL_VAR_INIT(rollovercheck_last_timeofday, 0)
 	if(second < 60)
 		return "[second] second[(second != 1)? "s":""]"
 	var/minute = floor(second / 60)
-	second = FLOOR(MODULUS(second, 60), round_seconds_to)
+	second = FLOOR(second %% 60, round_seconds_to)
 	var/secondT
 	if(second)
 		secondT = " and [second] second[(second != 1)? "s":""]"
 	if(minute < 60)
 		return "[minute] minute[(minute != 1)? "s":""][secondT]"
 	var/hour = floor(minute / 60)
-	minute = MODULUS(minute, 60)
+	minute %%= 60
 	var/minuteT
 	if(minute)
 		minuteT = " and [minute] minute[(minute != 1)? "s":""]"
 	if(hour < 24)
 		return "[hour] hour[(hour != 1)? "s":""][minuteT][secondT]"
 	var/day = floor(hour / 24)
-	hour = MODULUS(hour, 24)
+	hour %%= 24
 	var/hourT
 	if(hour)
 		hourT = " and [hour] hour[(hour != 1)? "s":""]"

code/modules/shuttle/docking.dm

@@ -41,7 +41,7 @@
 		rotation = dir2angle(new_dock.dir)-dir2angle(dir)
 		if ((rotation % 90) != 0)
 			rotation += (rotation % 90) //diagonal rotations not allowed, round up
-		rotation = SIMPLIFY_DEGREES(rotation)
+		rotation %%= 360
 
 	if(!movement_direction)
 		movement_direction = turn(preferred_direction, 180)

code/modules/vehicles/hardpoints/hardpoint.dm

@@ -696,7 +696,7 @@
 	if(muzzle_turf == target_turf)
 		return FALSE
 
-	var/angle_diff = SIMPLIFY_DEGREES(dir2angle(dir) - Get_Angle(muzzle_turf, target_turf))
+	var/angle_diff = (dir2angle(dir) - Get_Angle(muzzle_turf, target_turf)) %% 360
 	if(angle_diff < -180)
 		angle_diff += 360
 	else if(angle_diff > 180)