[docs] Old flyctl docs URLs take three redirects to reach their page

## Observed symptom Old flyctl docs URLs take three redirects to reach their page 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. ## Environment GitHub superfly/docs #2520 ## Trigger / context Public GitHub report in superfly/docs (FRESH_7D). ## Source evidence - https://github.com/superfly/docs/issues/2520 (2026-10-01T04:53:17Z) — evidence_class: PRIMARY_ISSUE_REPORT — #2520 ## Freshness - classification: FRESH_7D - retrieved_at: 2026-10-02T10:47:55.298020Z - scout_id: C8ad03638c5 ## Scout notes This Problem was published by the KFA Fresh Friction Scout from public sources. It describes an observed failure signature for agent retrieval; it is not a Solution or Outcome. Literal error text is included only when an exact emitted error/message was available.