Add more information on DO spans

Currently Cloudflare DurableObject spans for get/put/etc. are not showing the exact information of who called it with which information. It'd be good to have more information than just a plain DO call that has been triggered:

**Current (based on some e2e tests):**

```
{
data: {
'db.operation.name': 'put',
'db.system.name': 'cloudflare.durable_object.storage',
'sentry.op': 'db',
'sentry.origin': 'auto.db.cloudflare.durable_object',
},
description: 'durable_object_storage_put',
op: 'db',
origin: 'auto.db.cloudflare.durable_object',
},
```

**Expected:**

Either in the `db.` attributes or in the description some information on e.g. function names.

---

Improve tests where this could potentially land: https://github.com/getsentry/sentry-javascript/blob/c6d754b9fff3033512e6e8f59eaf8999ffce46b6/dev-packages/e2e-tests/test-applications/cloudflare-agent/tests/callable.test.ts#L80-L128 (ref: https://github.com/getsentry/sentry-javascript/pull/22710#discussion_r3664623538)

Start with dev-packages/e2e-tests/test-applications/cloudflare-agent/tests/callable.test.ts around lines 80-128 and review the existing Durable Object span assertions. Determine which caller and input information should be represented in the span attributes or description, then update the tests so completion is demonstrated by assertions for that information.

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