Slight rework of how tajaran watches work and new papercode for taj time (#21582)

This does a few times, after the scope got bigger than I originally
planned:
- Watches now have an action button top left to check time.
- Taj time checking code was moved over to the time helper file to not
be watch exclusive.
- The taj wrist watches now shows the time on adhomai.
- Papercode now has the ability to show taj time and date, and to insert
the credit symbol.

code/modules/background/origins/_origins.dm

@@ -43,3 +43,5 @@
 		old_origin.on_remove(src)
 	OI.on_apply(src)
 
+/singleton/origin_item/culture/proc/get_custom_time()
+	return FALSE

code/modules/background/origins/origins/tajara/adhomai.dm

@@ -48,6 +48,9 @@
 		/singleton/origin_item/origin/crevus
 	)
 
+/singleton/origin_item/culture/adhomian/get_custom_time()
+	return "Adhomian Time: [tajaran_time()], [tajaran_full_date()]"
+
 /singleton/origin_item/origin/hadiist_heartlands
 	name = "Hadiist Heartlands"
 	desc = "The Hadiist Heartlands include Nraz'i Basin, Ras'nrr Heartlands, East Ras'nrr, and Rhazar Mountains. In this region, the People's Republic's culture project was most successful. Its inhabitants are known for their political loyalty and adherence to the Party's teachings. In typical Republican fashion, the local culture places a large emphasis on the importance of the collective over the individual interest, with each Tajara being considered as a piece in the machinery of society."