AdguardTeam
[AGM-2726] Improve KB's structure a little
- Add root page for '/private-dns/setting-up-filtering/' section
- Move custom-domains.md to server-and-settings section
- Correct corresponding links and sidebar_position numbers in other articles
- Add missing subsection links in server-and-settings.md
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Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/
Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/
Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/
Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/
Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/
Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/
Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/
Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/
Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/
Preview was deployed to: https://pull-request-363.kb-dns.pages.dev/