[Load Balancing] Update docs for zone monitors

[gofish]

Update the list of zone-level features supported by and often require the use of Simulate Zone in Load Balancing.

Summary

Updates documentation regarding "Simulate Zone" in the

• Load Balancing FAQ
• Load Balancing Reference Architectures
• Load Balancing Monitor Advanced Settings

These updates correspond to feature support released in the 2026-08-06 Load Balancing Changlog.

Screenshots (optional)

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