Import Chronos timekeeping/scheduling library (vanilla 1.12)

Verbatim import of the Chronos addon from refaim's Vanilla WoW 1.12 addon
development libraries archive:
https://github.com/refaim/Vanilla-WoW-1.12-Addon-Development-Libraries-Archive (Libraries/Chronos)

Chronos is a hard dependency of CallOfElements (Chronos.scheduleByName/
startTimer/etc.). Hosting it as a standalone addon so the launcher can
install it alongside CoE.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

localization.en.lua

@@ -0,0 +1,8 @@
+-- Version : English (by Thott)
+-- Last Update : 02/17/2005
+
+-- Chat Configuration
+SCHEDULE_COMM		= {"/in","/pause","/delay"};
+SCHEDULE_DESC		= "/in <seconds> <command> [<args> ...] |cFFCC9966[Note: /in CANNOT cast spells to prevent creation of bots]|r";
+SCHEDULE_USAGE1		= "Usage: /in <seconds> <command> [<args> ...]";
+SCHEDULE_USAGE2		= "Runs <command> with arguments <args> after <seconds> seconds pass.";