Set /docs/pro as canonical Pro docs landing page

**Metr Tracking Issue**

**Category**: trivial
**Commits**: 1
**Lines changed**: 29 (+19/-10)
**Time span**: 0 hours

**PRs**:
- #20 - Set /docs/pro as canonical Pro docs landing page

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<summary>Commit details</summary>

- `1a5c9d2` Establish /docs/pro as canonical Pro docs landing page (#20) (+19/-10)

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