Release v0.16.2 - xchain-node carrier

[jdogresorg]

Carrier for the v0.16.2 patch train. The manifest is generated by bin/write-release-manifest.js from the actual tagged master merge commits, never by hand.

What moves

Component	Version
xchain-node	0.16.2
xchain-hub	0.16.2
xchain-indexer	0.16.1
everything else	v0.16.0, or v0.15.0 for xchain-vm, xchain-contracts, xchain-regtest-miner

Only xchain-hub moves in this train; xchain-indexer keeps the 0.16.1 it shipped under in the previous one.

Why

State-neutral hub fix. The llm attestation provider's default transport spawns a CLI by name, and resolveHubLlmAuth prefers that transport over an API key whenever HUB_CLAUDE_CONFIG_DIR is set, but the hub Dockerfile never installed the binary. Measured on BTC testnet: request 0dfcea87 was admitted at height 151599, ran about 90 consensus rounds over three hours, and expired at 151619 with zero responses, every seated hub reporting provider_error.

It was a rebuild-recurring regression rather than a one-time omission: the fleet ran for twelve days on a hand-built image carrying the binary, and the v0.16.0 roll rebuilt that tag from a Dockerfile that had never installed it. The fix is the recipe plus a guard that asserts the recipe rather than a running container.

No activation height moves and no derived state changes, so the rolling upgrade window cannot create a fork. A validator that serves no llm provider is unaffected.

Release commit audit

src/release-manifest.json (generated), package.json and package-lock.json version fields 0.16.1 to 0.16.2, the README version badge, and a CHANGELOG entry. Nothing else.

check-tag-version-parity --expect 0.16.2 --repos xchain-node: OK.

Component tags this manifest pins

Both pushed and verified before the manifest was generated, which is what the generator requires (tag exists at origin, reachable from that repo's origin/master, GPG-signed by the platform release key):

• xchain-hub v0.16.2 at 98dff5f, tagger releases@xchain.io, GitHub verified: true
• xchain-documentation v0.16.2 at 1b9b61f, tagger releases@xchain.io, GitHub verified: true