PackVerify only checks a single pack's own round-trip, which missed a
real bug: uiscript.eix entries were built without their required
"uiscript/" path prefix, so the standalone tool "round-tripped" fine
(source-relative paths matched its own wrongly-shifted reference) while
the actual game's CEterPackManager - which merges all packs into one
shared dict keyed by full path - failed to resolve any uiscript file.
PackManagerSim replicates the real client's PackInitialize(): it parses
the pack folder's Index manifest, registers every pack (~103) into one
real CEterPackManager exactly like the game does, and can verify every
entry of a given pack resolves through that full lookup path.
