xchain-explorer v0.19.0

xchain-explorer v0.19.0, part of the XChain Platform v0.19.0 train.

Bridge and policy panels render on the token and action pages, and the token read serves the
four bridge columns, so a cross-chain lock, burn or credit is readable where the token and
the action already are. The schema-mirror changelog states the hub-first roll order, since
the reader check is strict equality in both directions. Audited transitive packages move to
their patched releases (lockfile only). Restructured under the platform code-structure
standard; consensus identity byte-identical and pinned.

Full notes in CHANGELOG.md. The platform release with every component tarball is on xchain-node:
https://github.com/XChain-Platform/xchain-node/releases/tag/v0.19.0