One malformed or unreachable repo no longer hides the others; skip bad
index entries; a refreshed raw index outdates its reduced copy; style the
dialog like the others; validate package ids with PKG_RE.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Reducing an index no longer deletes apk-catalog/data/index-v2.json, which
the catalogue build reads. Drop the measurement log from docs.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>