fix(ci): twine upload --verbose --skip-existing

PyPI answered 429 to every first upload of a new project since the
afternoon of 2026-10-23; without --verbose the log does not say why or
for how long.

CHANGELOG.md

@@ -13,6 +13,8 @@ The format follows [Keep a Changelog](https://keepachangelog.com/), versions fol
   device-types pilot).
 
 ### Fixed
+- `publish` uploads with `--verbose`, so a refusal from PyPI shows its reason, and
+  `--skip-existing`, so a re-run after a partly successful upload does not fail.
 - The shared workflow waits 60 s per download and retries ten times, so a slow PyPI
   response no longer fails a job.
 - `ratchet` refuses a package directory that does not exist. Guessed from the name