Fixes #7743

/claim #7743

What

Public database exposure uses an nginx stream proxy generated in StartDatabaseProxy. Some users observe the TCP connection dropping around ~10 minutes.

This PR increases stream proxy timeouts so long-running downloads/queries can complete.

Changes

• Add proxy_connect_timeout 60s;
• Add proxy_timeout 12h;

Notes

• These are stream proxy timeouts, independent from Postgres statement timeouts.
• Follow-up could make this configurable in the UI if maintainers prefer.

Demo

(Will add a short demo video link here once I can capture it.)