chore: update redirect links

[nodejs-github-bot]

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[cursor]

PR Summary

Low Risk
Routine release metadata updates to JSON constants; no application logic changes.

Overview
Updates generated constants for the v26.4.0 Node release so “latest” URLs and symlink targets stay correct.

latestVersions.json now maps latest, latest-v26.x, and node-latest.tar.gz from v26.3.1 to v26.4.0. fileSymlinks.json retargets node-config-schema.json and llms.txt to the v26.4.0 docs paths. cachedDirectories.json registers the v26.4.0/ release directory (release and docs listings) and refreshes metadata for index.json, index.tab, and node-latest.tar.gz.

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