The comment at the install site claimed only that an overlapping worker result
'is discarded'. State why the empty-set result is installable at all — an empty
id intersection is proof a serial parse would have dropped nothing — and why the
tempting shortcut is wrong: parsedTurnsToCachedTurns delta-encodes gitBranch
across turns, so dropping one turn changes whether a LATER turn carries a
gitBranch key. Overlap discards the whole file, never individual turns.
Tests: the end-to-end determinism check now runs both parses over the SAME
corpus, so cache shard BODIES are compared byte for byte instead of just their
keys, and a new resumed-session fixture (a transcript restating another file's
message ids, in both filename orders) makes install order decide the answer.
Verified by mutation: removing the discard guard fails it, and yielding worker
results out of order fails it.
CODEBURN_VERBOSE now reports how many worker results were re-parsed in-process
on id overlap, which is what the new test asserts on. The worker bundle's source
map is excluded from the published package (-1.8 MB).
os.freemem() reports free pages on macOS, not available memory: on an idle
128 GB machine it reads a few hundred MB, so the 2 GB gate switched the worker
pool on and off between runs on the platform the desktop app ships to. The gate
and the budget now use process.availableMemory() (cgroup/rlimit-aware in a
container), falling back to os.totalmem(): serial under 4 GB available, budget
min(0.25 * available, 2 GB). An 8 GB box earns 8 threads, a 4 GB box none.
The verbose line now carries every decision input — cores, available GB, pending
files and bytes — on both the gate and the go path, so one support log explains
itself.
Pins the gates that keep threads off low-spec machines and warm runs, that a
forced worker count bypasses them, that results come back in submission order,
that a dead pool reports failure instead of throwing (and the serial fallback
lands on the same result), that no thread outlives a parse across back-to-back
parses, and that a cold CLI parse with and without workers produces the same
payload and the same cache shards.
