Old flyctl docs URLs take three redirects to reach their page

[alexleventer]

Found while checking the docs.fly.io move and confirmed. https://fly.io/docs/flyctl/deploy/ redirects to https://docs.fly.io/flyctl/deploy/ and then to https://docs.fly.io/flyctl/cmd/fly_deploy, and auth-login and mcp-server do the same. https://docs.fly.io/mcp returns 405.