First commit, step 4 completed

docs/annotations/Annotations/Core/Data/Classic.lua

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+---@meta
+--- cata, vanilla
+---@param spell number|string
+---@return number start
+---@return number duration
+---@return number enabled
+---@return number modRate
+---@overload fun(index: number, bookType: string)
+function GetSpellCooldown(spell) end