[Dashboard] Apply telemetry API limits in SQLite queries

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Describe the bug

The Dashboard telemetry API's spans, traces, and logs endpoints request `Count = int.MaxValue`, materialize every matching retained item, and only then apply the requested response limit.

A request for a small response can therefore still perform the full retained-data query and allocate the complete result.

### Expected Behavior

The requested response limit should bound repository paging and materialization. Total counts can be obtained separately when needed.

### Steps To Reproduce

1. Populate the Dashboard with retained logs or traces.
2. Request the corresponding telemetry API endpoint with a small `limit`.
3. Observe that the repository request still uses `Count = int.MaxValue` and the limit is applied after materialization.

### Exceptions (if any)

N/A

### Aspire doctor output

```plain
Aspire CLI 13.6.0-pr.18924.g5ee63941
Windows 10.0.26200
```

### Anything else?

Related to #18924. Source: `src/Aspire.Dashboard/Api/TelemetryApiService.cs:38-63,91-121,176-224`. This was acknowledged during PR review and remains on current `main`.

Start in src/Aspire.Dashboard/Api/TelemetryApiService.cs at lines 38-63, 91-121, and 176-224, and trace how the spans, traces, and logs endpoints request repository data. Verify that the requested limit is used for paging and materialization rather than int.MaxValue, while total counts are handled separately when needed. Done means small-limit requests no longer load all retained telemetry items.

Written by the indexing model from the issue text.