DefaultIcons

Pins the Cooldown Manager (Essential, Utility, Tracked Buffs, Buff Bars) to stock Blizzard art. Blizzard draws those icons itself, so the call-stack check that drives the rest of the addon can never attribute them to an addon folder — 2.2.0 therefore had no effect on them. They are now pinned by frame ownership: walk up from the texture region and pin anything living inside a *CooldownViewer frame. Two things this needed beyond the 2.2.0 aura code: icons an HD addon has already swapped to its own folder are now resolvable inside the Cooldown Manager (StockFor deliberately ignores addon paths everywhere else), and each viewer is re-swept after every Blizzard layout pass plus five paced passes over 15s, so a later HD write cannot win the race. Minimap buff/debuff pinning from 2.2.0 is kept but now defaults OFF and migrates off once. New: /dicons cd on|off|refresh and a Cooldown Manager checkbox in /dicons menu.