fix: rename currentRole to current-role in health check response (#3291)

## Why make this change?

The `/health` endpoint response used `currentRole` (camelCase) while
every other multi-word key in the response uses kebab-case (`app-name`,
`cache-ttl-seconds`, `response-ms`, etc.), creating an inconsistent API
surface.

## What is this change?

- Updated `[JsonPropertyName("currentRole")]` →
`[JsonPropertyName("current-role")]` in
`ComprehensiveHealthCheckReport.cs`.

**Before:**
```json
{
  "status": "Healthy",
  "app-name": "dab_oss_2.0.0",
  "currentRole": "anonymous"
}
```

**After:**
```json
{
  "status": "Healthy",
  "app-name": "dab_oss_2.0.0",
  "current-role": "anonymous"
}
```

## How was this tested?

- [ ] Integration Tests
- [ ] Unit Tests

## Sample Request(s)

```http
GET /health
```
Response now contains `current-role` instead of `currentRole`.

<!-- START COPILOT ORIGINAL PROMPT -->



<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>[Bug]: Health `currentRole` is inconsistent with the rest
of the health report</issue_title>
> <issue_description>## What?
> 
> Rename `currentRole` to `current-role` to have consistent naming. 
> 
> ### Current `/health` output
> 
> ```json
> {
>   "status": "Healthy",
>   "version": "2.0.0",
>   "app-name": "dab_oss_2.0.0",
>   "timestamp": "2026-03-15T21:29:03.3354392Z",
>   "currentRole": "anonymous", // this is what I am talking about
>   "configuration": {
>     "rest": true,
>     "graphql": true,
>     "mcp": true,
>     "caching": false,
>     "telemetry": false,
>     "mode": "Development"
>   },
>   "checks": [
> [snip]
>   ]
> }
> ````</issue_description>
> 
> ## Comments on the Issue (you are @copilot in this section)
> 
> <comments>
> </comments>
> 


</details>



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- Fixes #3285

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Aniruddh25 <3513779+Aniruddh25@users.noreply.github.com>

Author: Copilot

src/Service/HealthCheck/ComprehensiveHealthReportResponseWriter.cs

@@ -109,7 +109,7 @@ public async Task WriteResponseAsync(HttpContext context)
                     // Ensure cachedResponse is not null before calling WriteAsync
                     if (report != null)
                     {
-                        // Set currentRole per-request (not cached) so each caller sees their own role
+                        // Set current-role per-request (not cached) so each caller sees their own role
                         await context.Response.WriteAsync(SerializeReport(report with { CurrentRole = _healthCheckHelper.GetCurrentRole(roleHeader, roleToken) }));
                     }
                     else

src/Service/HealthCheck/Model/ComprehensiveHealthCheckReport.cs

@@ -46,7 +46,7 @@ public record ComprehensiveHealthCheckReport
         /// <summary>
         /// The current role of the user making the request (e.g., "anonymous", "authenticated").
         /// </summary>
-        [JsonPropertyName("currentRole")]
+        [JsonPropertyName("current-role")]
         public string? CurrentRole { get; set; }
 
         /// <summary>