chore: upstream dfinity/icp-cli-recipes (motoko) moved to motoko-v5.1.0

[pr-automation-bot-public]

dfinity/icp-cli-recipes has moved past the ref the docs are verified against.

Pinned in .sources/upstream.json	motoko-v5.0.0
Latest release	motoko-v5.1.0
Compare	dfinity/icp-cli-recipes@motoko-v5.0.0...motoko-v5.1.0
Published reference	https://github.com/dfinity/icp-cli-recipes/releases

What to re-check

Cited in 3 places as the Motoko canister recipe in icp.yaml examples. Each recipe in this repo tags and releases on its own prefix, so it gets its own entry: a single pattern across prefixes would compare rust- against static-site- textually and only ever surface one of them.

How to close this

1. Review the changes above against the pages named under "What to re-check".
2. Update those pages if anything they state has changed.
3. Set pinned to motoko-v5.1.0 in .sources/upstream.json in the same PR.

If nothing in the docs is affected, bump the pin on its own and say so in the PR.

Procedure: .agents/upstream-tracking.md

[marc0olo]

Done in #370. Same additive visibility change; 3 occurrences of @dfinity/motoko@v5.0.0 are now @v5.1.0. Pin moved to motoko-v5.1.0.