Fetch a single social profile by (platform, username).
Always use this first when the user gives an exact handle on a specific platform
(for example "@niickjackson on Instagram") and you need the full profile: bio,
follower/engagement metrics, recent activity, growth, and the canonical creator ID.
Pass exactly the username they typed without the @ sign — case-insensitive matching is
handled server-side. Do not use `search_creators` for an exact platform+username
lookup.
Examples:
- User: "Pull @niickjackson on Instagram" -> use this tool with platform
"instagram" and username "niickjackson".
- User: "Tell me about instagram.com/niickjackson" -> parse the platform and
username, then use this tool.
- User: "Is @niickjackson a fit for Pixel?" -> use this tool first, then call
`get_posts` and/or `match_creators` if the task needs content or fit analysis.
Returns the profile record plus the underlying creator record. If you already have a
creator UUID, use `get_creator` instead. For batch lookups by handle, use
`lookup_profiles`.