Area-based Horizon lighting (#22511)

This adds unique lighting palettes to different areas of the SCCV
Horizon. It does this by tying randomized_lighting variable for light
fixtures to the department variable of the area they are in. This
solution is intended to save a lot of time and effort, both now and
later, which would otherwise be spent mapping down each colour of
lighting into every department manually.

Notable points:
- This shifts the parent colour for light bulbs from LIGHT_COLOR_HALOGEN
(#C0C0CA) to the new LIGHT_COLOR_OFFWHITE (#efe5bb), and shifts the
randomized_colors variable to the according list. This shifts them from
a slightly murky blue-tinted white to a slightly brighter yellow-tinted
white. Slightly warm lighting will now be the default for every map.
Warmer lighting communicates the age of a ship or station, the worsening
economic prospects of the setting, and it's also a bit cosier.
- Stark white lighting is retained for medical and the bridge. Research
has been given purple-tinted lighting.
- Command offices are also under blue lighting currently, to visually
differentiate them from the rest of their departments.
- To avoid too much player-facing bloat, only a box for pale purple has
been added so janitors can replace the lighting in research. Otherwise,
yellow can be used for engineering, white for public areas, and blue for
high-security areas.
- Offsites and offships shouldn't be hugely changed by the shift in
default lighting - it's a slight change in hue.

Screenshots below!
<details>
<img width="1077" height="1080" alt="image"
src="https://github.com/user-attachments/assets/1987e29f-c34c-44ea-865f-5f81c0e5c47f"
/>
<img width="1080" height="1080" alt="image"
src="https://github.com/user-attachments/assets/79279c6c-da56-4676-a0e9-7e5db43002cd"
/>
<img width="1083" height="1080" alt="image"
src="https://github.com/user-attachments/assets/621589b5-ada6-4d80-9f8f-8cf13a47df39"
/>
<img width="1085" height="1080" alt="image"
src="https://github.com/user-attachments/assets/09284700-8408-4a86-86c5-7575e7c94a27"
/>
<img width="1081" height="1080" alt="image"
src="https://github.com/user-attachments/assets/8246585c-f437-437a-8d32-9997fae05298"
/>
<img width="1078" height="1080" alt="image"
src="https://github.com/user-attachments/assets/a34841dd-3f49-4010-b2e0-d2e9a748e617"
/>
<img width="1084" height="1080" alt="image"
src="https://github.com/user-attachments/assets/55e89703-8ac7-4fa7-9775-19818c10c119"
/>
<img width="1080" height="1080" alt="image"
src="https://github.com/user-attachments/assets/684dea04-90c5-4877-b2bf-08a2146efb5e"
/>
<img width="1078" height="1080" alt="image"
src="https://github.com/user-attachments/assets/6ce42ac1-0f4b-49eb-8f2c-c6fb1830877e"
/>
<img width="1083" height="1080" alt="image"
src="https://github.com/user-attachments/assets/bc41a4f4-8d5c-4348-b9fe-a41d7950ce37"
/>
<img width="1081" height="1080" alt="image"
src="https://github.com/user-attachments/assets/48c4b733-a375-482b-9f70-e2aa6d0b3e27"
/>
<img width="1083" height="1080" alt="image"
src="https://github.com/user-attachments/assets/52e0041a-602d-4f4b-9d6c-7d0a0946f90b"
/>
</details>

code/game/objects/items/weapons/storage/boxes.dm

@@ -873,7 +873,7 @@
 		/obj/item/light/tube/colored/blue,
 		/obj/item/light/tube/colored/magenta,
 		/obj/item/light/tube/colored/yellow,
-		/obj/item/light/tube/colored/cyan
+		/obj/item/light/tube/colored/pale_purple
 	)
 	var/static/list/bulbs_colors = list(
 		/obj/item/light/bulb/colored/red,
@@ -881,7 +881,7 @@
 		/obj/item/light/bulb/colored/blue,
 		/obj/item/light/bulb/colored/magenta,
 		/obj/item/light/bulb/colored/yellow,
-		/obj/item/light/bulb/colored/cyan
+		/obj/item/light/bulb/colored/pale_purple
 	)
 	for(var/i = 0, i < 14, i++)
 		var/type = pick(tube_colors)
@@ -920,6 +920,12 @@
 	color = COLOR_YELLOW_GRAY
 	starts_with = list(/obj/item/light/tube/colored/yellow = 14, /obj/item/light/bulb/colored/yellow = 7)
 
+/obj/item/storage/box/lights/colored/pale_purple
+	name = "box of pale purple lights"
+	illustration = "lightmixed"
+	color = COLOR_PURPLE_GRAY
+	starts_with = list(/obj/item/light/tube/colored/pale_purple = 14, /obj/item/light/bulb/colored/pale_purple = 7)
+
 /obj/item/storage/box/lights/colored/magenta
 	name = "box of magenta lights"
 	illustration = "lightmixed"

code/game/objects/random/loot.dm

@@ -116,6 +116,7 @@
 		/obj/item/storage/box/lights/colored/cyan = 0.1,
 		/obj/item/storage/box/lights/colored/green = 0.1,
 		/obj/item/storage/box/lights/colored/magenta = 0.1,
+		/obj/item/storage/box/lights/colored/pale_purple = 0.1,
 		/obj/item/storage/box/lights/colored/red = 0.1,
 		/obj/item/storage/box/lights/colored/yellow = 0.1,
 		/obj/item/storage/box/lights/coloredmixed = 0.2,

code/game/objects/structures/machinery/lightswitch.dm

@@ -103,10 +103,10 @@
 /obj/structure/machinery/light_switch/idris
 	name = "idris smart switch"
 	desc = "A smart lightswitch designed by Idris Incorporated for entertainment venues, this one has additional controls for adjusting the color and brightness of the compartment's lighting."
-	var/current_light_color = LIGHT_COLOR_HALOGEN
+	var/current_light_color = LIGHT_COLOR_OFFWHITE
 	var/current_brightness = 1.0
 	var/static/list/color_options = list(
-		"Standard" = LIGHT_COLOR_HALOGEN,
+		"Standard" = LIGHT_COLOR_OFFWHITE,
 		"Red" = LIGHT_COLOR_RED,
 		"Green" = LIGHT_COLOR_GREEN,
 		"Blue" = LIGHT_COLOR_BLUE,