Moves the four extracted-Data-tree audit handlers out of main:
--info-extract (per-extension counts + bytes)
--info-extract-tree (per-directory rollup)
--info-extract-budget (proprietary share + open-format gap)
--list-missing-sidecars (find unconverted .m2/.wmo/.blp/.dbc)
All four operate on a Blizzard-format extracted Data tree —
they audit what's there and what's missing in the migration
from proprietary formats to open ones.
main.cpp drops 13,485 → 13,120 lines (-365). Behavior verified
by re-running --info-extract on a test zone (same output).
