Fix unregistered and hijacked external links in documentation

[ppkarwasz]

What

Fixes two external documentation links that point at domains not controlled by the projects they claim to reference:

1. Citrus link typo — docs/user-manual/modules/ROOT/pages/testing.adoc linked to citfrusframework.org instead of citrusframework.org. The misspelled domain is unregistered (verified via RDAP on 2026-08-25), so anyone could register it and serve arbitrary content to readers — and to AI agents that consume the generated https://camel.apache.org/manual/testing.md / llms.txt files — under the authority of the Camel documentation. Introduced in 67a4e62 (chore(docs): Improve integration testing documentation #18883); reported to security@apache.org by an external researcher and triaged as a documentation fix rather than a vulnerability.

2. Hijacked snakeyaml.org — the SnakeYAML docs and Javadoc linked to www.snakeyaml.org, but that domain lapsed and was re-registered on 2025-01-01 by an unrelated third party that now serves an SEO content site trading on the SnakeYAML name. The links now point to the project's real home at https://bitbucket.org/snakeyaml/snakeyaml. The catalog copy of the doc page (a verbatim sync of the source .adoc) was updated to match.

Verification sweep

All ~400 external domains referenced across the documentation tree were checked for: look-alike misspellings (edit-distance comparison), unregistered domains (DNS + RDAP), nameservers pointing at domain-parking services, RDAP re-registration dates newer than the doc references, and "for sale" landing pages. No other compromised or claimable real-project domain was found. Notes for potential follow-ups (not security-relevant, so left out of this PR): kaotoio.github.io/kaoto/ in getting-started.adoc is a dead GitHub Pages link (the KaotoIO org still exists, so it is not takeover-able), and random-data-api.com (used in JBang examples) no longer serves DNS but remains registered until 2027.

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This PR was created by Claude Code on behalf of ppkarwasz.

🤖 Generated with Claude Code

https://claude.ai/code/session_015JZf5SuQcZsKEyX9MRWMbh

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