[stats]: consistency patchwork

[Anish-Agnihotri]

With becoming the de-facto statistics website and increased traffic, it's become important to maintain correctness:

• Update sync process with better failovers and escalating restarts
• Ensure all relays have correctly recorded data (see: potentially BloXRoute, Blocknative inconsistencies)
• Manually verify reported payload value responses from relays
• Migrate stats service to better, hands-off infrastructure provider
• Add site uptime tracking and alerts
• Filter default builder public key by builder address