docs: remove cli beta warning

[uinstinct]

Description

Remove the beta warning from cn cli since it is now out of beta

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Checklist

• [] I've read the contributing guide
• [] The relevant docs, if any, have been updated or created
• [] The relevant tests, if any, have been updated or created

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Tests

[ What tests were added or updated to ensure the changes work as expected? ]

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Summary by cubic

Removed the beta warning from the Continue CLI (cn) docs to reflect that it’s no longer in beta. This avoids confusion and keeps the page consistent with the current status.

^{Written for commit e38b997. Summary will update automatically on new commits.}

[cubic-dev-ai]

No issues found across 1 file

[RomneyDa]

@uinstinct this PR appears to be in a broken state