Handle scanner POSTs to catch-all routes as not found

[kentcdodds]

Summary

• Patch the deployed epicshop workshop runtime after install so the root routes/$ module has an action that returns the same 404 behavior as its loader.
• Update the not-found splat route solution and exercise copy to handle non-GET missing-route requests as 404s.
• Add focused coverage for POSTs to scanner-style missing paths and for the runtime patcher.
• Refresh the existing not-found exercise smoke assertion to match the page’s current Epic Notes heading.

Sentry

• References epicshop Sentry issue EPICSHOP-F0 / 7447885629.
• Targets noisy getInternalRouterError events from scanner POSTs like /connectors/resource/index.php and /assets/components/gallery/connector.php without suppressing unrelated router errors.

Validation

• npm test in epicshop passes.
• npm run typecheck passes.
• npm test -- --project=chromium tests/e2e/smoke.test.ts in exercises/07.error-handling/05.solution.not-found passes.