docs: clarify domain overrides and add Network Error troubleshooting

[mintlify]

Tightens the AWS Private API Connectivity doc around the question Lyft raised in BYOC onboarding ("what do domain overrides do?" + UI "Network Error" when overrides are set).

Changes

admin/deployment/dedicated/aws/private-api-connectivity.mdx

• Configuring the private domain — added an explicit explanation of what domain overrides actually do: they are a string Cube embeds when generating outbound references (UI links, SLS configs, API page details) so the browser / BI client / app dials the private hostname directly. They do not open a new tunnel from Cube's control plane.
• Troubleshooting "Network Error" in the Cube UI — new section that walks through Maksim's debugging recipe:
  1. Open DevTools Network tab, find the failing request to the private hostname.
  2. Open that URL in a new tab and read the actual browser error (DNS, TCP, TLS, or HTTP).
  3. Confirm the same request works from inside the VPC to isolate VPN/route issues.
  4. Sanity-check the override value (no scheme, matches DNS, matches cert, can be cleared to fall back to public).
• Replaced the earlier short <Warning> callout with a link into the new section.

[mintlify]

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Project	Status	Preview	Updated (UTC)
cubed3	🟢 Ready	View Preview	Jun 4, 2026, 5:46 PM

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