Detect the dispel talents instead of asking for them

The three talents that grant an extra dispel type were gated behind
manual checkboxes because the talent state looked unreadable on this
server. It isn't: C_CharacterAdvancement.GetTalentRankByID reports a
live rank for the player, entry IDs are shared across every class tree
so querying a foreign one just reports rank 0, and
CHARACTER_ADVANCEMENT_UPDATE_ENTRIES_RESULT fires when a build is
confirmed.

Key the talents to their entry IDs and read them instead. The lookup is
cached, since PostUpdate_DebuffHighlight runs once per aura per frame,
and refreshed on build confirmation plus the existing delayed refresh
after login. Every call is guarded, so a missing API reads as "talent
not taken" and behaves as it did before.

The three checkboxes are gone, replaced by a single Detect Talents
switch that turns the whole lookup off.

README.md

@@ -8,7 +8,7 @@ ElvUI plugin that hides and skins the custom CoA (3.3.5) frames not covered by s
 - Class resource frames: hiding
 - Extra action button frame: skin, anchor, size
 - Instance swap frame: skin, anchor, font settings
-- Only highlight unitframes if dispellable by your CoA class, with manual talent switch.
+- Only highlight unitframes if dispellable by your CoA class.
 
 ## Installation