The handler in question when called for tablets-enabled keyspace, returns ranges that are inconsistent with those from system.tablets. Like this:
system.tablets:
```
TabletReplicas(last_token=-4611686018427387905, replicas=[('e43ce450-2834-4137-92b7-379bb37684d1', 0), ('67c82fc2-8ef9-4dd9-8cf6-c7f9372ce207', 0)])
TabletReplicas(last_token=-1, replicas=[('22c84cba-d8d0-4d20-8d46-eb90865bb612', 0), ('67c82fc2-8ef9-4dd9-8cf6-c7f9372ce207', 1)])
TabletReplicas(last_token=4611686018427387903, replicas=[('22c84cba-d8d0-4d20-8d46-eb90865bb612', 1), ('67c82fc2-8ef9-4dd9-8cf6-c7f9372ce207', 1)])
TabletReplicas(last_token=9223372036854775807, replicas=[('e43ce450-2834-4137-92b7-379bb37684d1', 1), ('22c84cba-d8d0-4d20-8d46-eb90865bb612', 0)])
```
range_to_endpoint_map:
```
{'key': ['-9069053676502949657', '-8925522303269734226'], 'value': ['127.110.40.2', '127.110.40.3']}
{'key': ['-8925522303269734226', '-8868737574445419305'], 'value': ['127.110.40.2', '127.110.40.3']}
...
{'key': ['-337928553869203886', '-288500562444694340'], 'value': ['127.110.40.1', '127.110.40.3']}
{'key': ['-288500562444694340', '105026475358661740'], 'value': ['127.110.40.1', '127.110.40.3']}
{'key': ['105026475358661740', '611365860935890281'], 'value': ['127.110.40.1', '127.110.40.3']}
...
{'key': ['8307064440200319556', '9117218379311179096'], 'value': ['127.110.40.2', '127.110.40.1']}
{'key': ['9117218379311179096', '9125431458286674075'], 'value': ['127.110.40.2', '127.110.40.1']}
```
Not only the number of ranges differs, but also separating tokens do not match (e.g. tokens -2 and 0 belong to different tablets according to system.tablets, but fall into the same "range" in the API result).
The source of confusion is that despite storage_service::get_range_to_address_map() is given correct e.r.m. pointer from the table, it still uses token_metadata::sorted_token() to work with. The fix is -- when the e.r.m. is per-table, the tokens should be get from token_metadata's tablet_map (e.g. compare this to storage_service::effective_ownership() -- it grabs tokens differently for vnodes/tables cases).
This PR fixes the mentioned problem and adds validation test. The test also checks /storage_service/describe_ring endpoint that happens to return correct set of values.
The API is very ancient, so the bug is present in all versions with tablets
Fixes#26331Closesscylladb/scylladb#26231
* github.com:scylladb/scylladb:
test: Add validation of data returned by /storage_service endpoints
test,lib: Add range_to_endpoint_map() method to rest client
api: Indentation fix after previous patches
storage_service: Get tablet tokens if e.r.m. is per-table
storage_service,api: Get e.r.m. inside get_range_to_address_map()
storage_service: Calculate tokens on stack
efd99bb0af