* fix(cli): route skills list output to stdout when --json is active
runSkillsAction used defaultRuntime.log() which goes through console.log.
The --json preAction hook calls routeLogsToStderr(), redirecting console.log
to stderr. Switch to defaultRuntime.writeStdout() which writes directly to
process.stdout, consistent with how other --json commands (e.g. skills search)
already emit their output.
Fixes#57599
* test(cli): add skills JSON stdout regression coverage
* test(cli): refine skills CLI stream coverage
* fix(cli): add changelog entry for skills JSON stdout fix
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Co-authored-by: Aftabbs <aftabbs.wwe@gmail.com>
