Add BCE temporal tags to all documents; add temporal-dating steering doc

cities/troy.md

@@ -4,22 +4,22 @@
 # Troy
 
 ## Overview
-Troy (ancient Ilion/Ilium) was a Bronze Age city in northwestern Anatolia, famous as the setting of Homer's *Iliad*. The archaeological site at Hisarlik reveals multiple occupation layers spanning ~3000 BCE to the Roman period.
+Troy (ancient Ilion/Ilium) was a Bronze Age city in northwestern Anatolia, famous as the setting of Homer's *Iliad*. The archaeological site at Hisarlik reveals multiple occupation layers spanning ~3000 BCE to the Roman period. @t[~3000 BCE]
 
 ## Key Facts
 - Location: Hisarlik, Çanakkale Province, Turkey
-- Period: ~3000 BCE – Roman era
+- Period: ~3000 BCE – Roman era @t[=000 BCE]
 - Excavated by: Heinrich Schliemann (1870s), Wilhelm Dörpfeld, Carl Blegen, Manfred Korfmann
 - UNESCO World Heritage Site since 1998
 
 ## Archaeological Layers
-- Troy I–V (~3000–1750 BCE): Early Bronze Age settlements
-- Troy VI (~1750–1300 BCE): Major fortified city, likely the Homeric Troy [^1]
-- Troy VIIa (~1300–1180 BCE): Destroyed by fire; candidate for the Trojan War destruction
+- Troy I–V (~3000–1750 BCE): Early Bronze Age settlements @t[3000 BCE..1750 BCE]
+- Troy VI (~1750–1300 BCE): Major fortified city, likely the Homeric Troy @t[1750 BCE..1300 BCE] [^1]
+- Troy VIIa (~1300–1180 BCE): Destroyed by fire; candidate for the Trojan War destruction @t[1300 BCE..1180 BCE]
 - Troy VIII–IX: Greek and Roman Ilion
 
 ## The Trojan War
-- Traditionally dated ~1184 BCE (Eratosthenes' calculation)
+- Traditionally dated ~1184 BCE (Eratosthenes' calculation) @t[~1184 BCE]
 - Homer's *Iliad* describes a Greek siege of Troy over the abduction of Helen
 - Historical basis debated; may reflect Bronze Age conflicts between Mycenaeans and Anatolian powers [^2]