The driver flip moves build artifacts from next-to-source <stem>.s to a
.sepwork/ scratch dir. 29 Pattern-B gates now build `ww build --sep -o <stem>`
and read <stem>.sepwork/__root.s (multi-package gates concat all
<stem>.sepwork/*.s, since cross-package labels live in per-package .s).
All intermediates redirect to /tmp (WW_PKGCACHE + -o), so the corpus runs
parallel-safe with no source-tree pollution. Tests pass now (--sep is live)
and survive the flip.
915 additionally retargeted off strconv's PRIVATE left_shift_table (a let,
not export) — which separate compilation correctly hides — onto a test-local
package that exports its own probe table (#96). The combined path only linked
it via a single-unit private leak; encapsulation is now honored under sep.
Test-only; all 5 *_ww binaries HOLD. 989_m1mangle_run deferred (blocked by
#99, imported-package fn main mangling under sep).
Hojun-Cho
eb6083e54a