Every surviving carrier now owns its artifacts: checked mkdir/mkdtemp/
fopen acquisition, one all-exit cleanup funnel per carrier, ENOENT-
tolerant checked unlinks, exact-path deletion (rm -rf only for an
owned pid-keyed dir or a .sepwork beneath one), and cleanup failure
fails a passing carrier without overwriting its diagnostic. In the
same pass the carriers adapt to the driver contract this branch lands:
--sep and WW_PKGCACHE are gone, -S and the /tmp/ww_run_<pid> scratch
contract are asserted, and rows whose runtime or reject coverage moved
to test/wcc/data fixtures or test/lang @test owners are trimmed to the
byte/artifact/diagnostic observations only they can make.
Repair and adaptation ride together because most files interleave both
in the same hunks; splitting would manufacture intermediate carrier
states that never existed and cannot run against either driver.
BUG-A #9: when an empty/export-less inlined module body produces `//ww:module <p>` immediately followed by `//ww:module-reset` in one skipws run, lexnext drained TK_MODRESET first then emitted the STALE TK_MODPATH past the reset boundary, re-binding pathmod=<p> so the root `package main` was validated against <p> -> wrong reject. Fix clears the pending modpath at the reset-RECOGNITION site in skipws (NOT lexnext drain): cstage l->modpath=NULL after both l->modreset=1 (cmd/wcc/lex.c); selfhost l.modpathset=0 after all three l.modreset=1 (lib/ww/syntax/lex.ww). Symmetric (rule-10): identical token streams, bootstrap byte-id holds. The normal RESET-then-PATH boundary is unaffected (clear is a no-op when no path is pending). Pin: test/wcc/989_modresetadj_run.c feeds the raw composed adjacency to w6c+w6c_ww (accept + byte-id), red-path-proven (reverting a clear reddens it). A separate wwi-producer defect surfaced (decl-less .wwi defaults to 'package main') filed as #11; not touched here.
