Add redirects for removed system tables pages

[Blargian]

Summary

Adds redirects for two pages which were removed without adding redirects. Reported via community here: https://clickhousedb.slack.com/archives/CU478UEQZ/p1754772495010949
Requires ClickHouse/ClickHouse#85550

Checklist

• Delete items not relevant to your PR
• URL changes should add a redirect to the old URL via https://github.com/ClickHouse/clickhouse-docs/blob/main/docusaurus.config.js
• If adding a new integration page, also add an entry to the integrations list here: https://github.com/ClickHouse/clickhouse-docs/blob/main/docs/integrations/index.mdx

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Project	Deployment	Preview	Comments	Updated (UTC)
clickhouse-docs	✅ Ready	Preview	Comment	Aug 13, 2025 2:34pm

3 Skipped Deployments

Project	Deployment	Preview	Comments	Updated (UTC)
clickhouse-docs-jp	⬜️ Ignored			Aug 13, 2025 2:34pm
clickhouse-docs-ru	⬜️ Ignored			Aug 13, 2025 2:34pm
clickhouse-docs-zh	⬜️ Ignored			Aug 13, 2025 2:34pm