docs: Update versions in versions1.json with new releases

[balasaajay]

What does this PR do ?

Update versions in versions1.json with new releases

Changelog

• Add specific line by line info of high level changes in this PR.

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Additional Information

• Related to # (issue)

[claude]

LGTM — docs-only change to the version-switcher dropdown (docs/versions1.json).

Verified:

• JSON is well-formed and the new 0.6.0 / 0.5.1 / 0.5.0 entries follow the existing schema.
• Exactly one preferred:true entry (0.6.0), and (latest) moved from 0.4.2 to 0.6.0 consistently.
• 0.4.2 URL correctly repinned from the shared /latest/ alias to /0.4.2/, so it resolves to its own archived docs rather than tracking latest.

No functional/source code touched.

Suggested test cases

• No perf tests impacted.