Low-code comparison monitors

We've redesigned and rebuilt comparison monitors with a focus on usability. The new experience supports:

• Monitor creation without writing SQL
• Comparing multiple metrics in a single monitor
• Cloning monitors and changing table selection while preserving alert conditions
• Automatic runs when target tables or data sources are updated
• Simpler debugging with visibility into which warehouse triggered an error
• Increased limit from 100 to 500 field/metric/segments tracked
• Clearer results, alerts, and notifications