Merge master 0e9385ad8b9e75146f4baec2e731dd961f11c87c, observed when
this final integration step started, into the merged V4 release branch.
Keep the complete upstream history and do not advance to later master
commits during finalization.
Bring the Web trust-domain and relative-route handling, plugin install
cancellation, and npm registry mirror configuration into the common
release baseline. Retain the V4 codecs, producer-source policy,
parent-owned catalogs, and fork/migration behavior from the merged stack.
The merge needs no manual conflict resolution and changes no Session
JSONL inputs, snapshot generations, format packages, or persistence
schema/history files. This checkpoint precedes the separate V4 freeze
and audit fixes so each change keeps its own rationale and validation.
Tianyi Cui
498d0e8ecd