fix: use custom error component with Sentry error reporting for 500s

[brandonroberts]

Description

• Switches the 500.tsx page to a custom _error.tsx file and enable Sentry error reporting
• This goes along with enabling source maps for Sentry to give more details about errors

Related Tickets & Documents

Closes #4049

Mobile & Desktop Screenshots/Recordings

Steps to QA

Tier (staff will fill in)

• [ ] Tier 1
• [ ] Tier 2
• [ ] Tier 3
• [x] Tier 4

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