Fix worker spec typing in npm build - #1

…nned

Four verdicts: (1) global buckets exonerated — pinned comparison shows no
penalty in any region/op/size; (2) us-east-1/iad has a sustained
Tigris-internal write problem (1KB PUT sp50 110-260ms for 15 straight
hours, both bucket types, their own Server-Timing header); (3) TLS setup
to t3.storage.dev costs 96-155ms from fra/cdg/ewr/sjc Compute vs 10-14ms
from sin/nrt — PoP routing question shared with Compute networking;
(4) write tails punish SPARSE traffic: hourly 16-conc bursts run FASTER
than 0.1Hz solo probes in the same hours (p99 deltas up to -3.3s) —
retires the strong time-of-day hypothesis, poses the what-idles-out
question to Tigris.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>