Add java platform URLs to mise.lock

A prior mise.lock regeneration left the core:java entry with only
[tools.java.options] and no per-platform url/checksum entries. Under
the mise version used in CI, 'mise install --locked' then fails with
'No lockfile URL found for java@26.0.1', which broke the gh-pages
deploy (it runs the full locked install). Regenerated with 'mise lock
java' to populate the per-platform entries.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: oschwald