Makes node selection zone-aware instead of drawing from one global
pool for every hotspot. Includes real herb/ore entries verified
against the live acore_world database for all four configured
hotspots (Un'Goro Crater, Winterspring, Eastern Plaguelands, Sholazar
Basin), plus a rare 'bonus' tier per zone (Black Lotus for the three
Classic zones -- a real, accurate spawn-zone match, not an arbitrary
pick).
Extends the existing pipe-delimited ZonePool config format with two
optional segments rather than introducing a new config key, and
explicitly calls out backward compatibility for hotspots that don't
specify zone-specific resources.
