fix: operations category sidebar

[vinckr]

• Moves Operations documents from "main" category to Guides and Reference
• Creates Operation sidebar similar to other guide categories

Documents in Operations guides:

• "guides/manage-project-via-api",
• "console/change-owner",
• "guides/gitops",
• "actions/live-events",

Documents in Operations reference:

• "concepts/personal-access-token",
• "guides/cors",
• "guides/custom-domains",
• "guides/rate-limits",
• "guides/ip-allowlist",
• "api/eventual-consistency",
• "guides/custom-domains",
• "console/usage-billing",

I am not sure "Operations" is the best sidebar title in the main sidebar, let me know if you have a better idea (DevOps?)

Related Issue or Design Document

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