ref(node): Remove vendored Hapi instrumentation (#22750)

## What

Removes the dead OpenTelemetry `HapiInstrumentation` (and
`instrumentHapi`) plus its vendored code from `@sentry/node`. Keeps
`setupHapiErrorHandler`.

## Why

The Hapi integration is now provided by the channel-based implementation
in `@sentry/server-utils` (the default since #22501). The vendored
instrumentation is no longer wired up; only the Sentry-specific error
handler remains user-facing.

Ref: #22346

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: andreiborza

packages/node/src/integrations/tracing/hapi/index.ts

@@ -1,14 +1,8 @@
-import { HapiInstrumentation } from './vendored/instrumentation';
 import { captureException, debug, getDefaultIsolationScope, getIsolationScope, SDK_VERSION } from '@sentry/core';
-import { generateInstrumentOnce } from '../../../otel/instrument';
 import { ensureIsWrapped } from '../../../utils/ensureIsWrapped';
 import { DEBUG_BUILD } from '../../../debug-build';
 import type { Request, RequestEvent, Server } from './types';
 
-const INTEGRATION_NAME = 'Hapi' as const;
-
-export const instrumentHapi = generateInstrumentOnce(INTEGRATION_NAME, () => new HapiInstrumentation());
-
 function isErrorEvent(event: unknown): event is RequestEvent {
   return !!(event && typeof event === 'object' && 'error' in event && event.error);
 }