Pure tombstone events duplication

### Integration

sentry-android

### Build System

Gradle

### AGP Version

8.14.0

### Proguard

Enabled

### Other Error Monitoring Solution

No

### Version

8.44.1

### Steps to Reproduce

Unfortunately, I was unable to reproduce this problem on local devices.

### Expected Result

Tombstone events are not duplicated.

### Actual Result

I see duplicate events in the reports received from users:

I downloaded two event's jsons and compared:
```
E:\work\tmp>diff "l.txt" "r.txt"
2c2
< "event_id": "b4a16e59fd854caaa8ebae2ea2828dd0",
---
> "event_id": "5716230e7f254ec9b3bcfe13d562bde2",
6893,6894c6893,6894
< "nodestore_insert": 1788397282.7622,
< "received": 1788397276.54076,
---
> "nodestore_insert": 1788358349.59206,
> "received": 1788358346.52165,
```
All content is identical, except from id and received time.

Therefore, I assume there is a bug when same tombstone may be reported twice.

P.S. Ignore the fact that the "Release" field is missing from the events - that's another issue I started to address, but noticed duplicates. For some reason, pure tombstone events don't have custom tags, breadcrumbs and attachment. If someone knows the reason, please advice, any hints are highly appreciated.

Start with the sentry-android tombstone reporting path and compare the two supplied event JSONs, focusing on why identical content is received twice. Reproduce the reported Android and Gradle setup if possible; done means a single tombstone produces one event, with the duplicate-event behavior covered by an appropriate test.

Vom Indexierungsmodell aus dem Issue-Text verfasst.