extract: scan way nodes once across all extracts in complete_ways pass 1

[yuiseki]

See #312.

In Pass 1 of --strategy=complete_ways, eway() is called independently for
each extract on every way. This means way.nodes() is scanned up to twice per
extract, giving up to 2N scans total for N extracts.

This adds an eway_all() override in strategy_complete_ways that scans
way.nodes() at most twice regardless of N. A uint64_t bitmask tracks which
extracts have claimed the way in the first pass; the second pass then records
all node refs into extra_node_ids for matched extracts only.

When there are more than 64 extracts the method falls back to the original
per-extract eway() loop.

Benchmark

japan-260423.osm.pbf (~1 GB), 8-tile extraction:

Version	Elapsed	vs baseline
upstream	1m 29s	—
this PR	1m 25s	-4%

planet-260413.osm.pbf (~86 GB), 16-tile extraction:

Version	Elapsed	vs baseline
upstream	51m 36s	—
this PR	49m 27s	-4%

Output verified to be identical to the upstream result for all tiles.