chore(app): Add configurable exclusions for feature metric tracking (#2753)

## Related Issue(s)

- #2376

## Verification

- [x] **Your** code builds clean without any errors or warnings
- [x] Manual testing done (required)
- [ ] Relevant automated test added (if you find this hard, leave it and
we'll help out)

Author: knuhau

src/Digdir.Domain.Dialogporten.WebApi/Common/FeatureMetric/FeatureMetricMiddleware.cs

@@ -1,16 +1,25 @@
 using Digdir.Domain.Dialogporten.Application.Common.Behaviours.FeatureMetric;
+using Microsoft.Extensions.Options;
 
 namespace Digdir.Domain.Dialogporten.WebApi.Common.FeatureMetric;
 
 /// <summary>
 /// Middleware to handle feature metric delivery acknowledgments based on HTTP response status codes
 /// </summary>
-public sealed class FeatureMetricMiddleware(RequestDelegate next)
+public sealed class FeatureMetricMiddleware(RequestDelegate next, IOptions<FeatureMetricOptions> options)
 {
     private readonly RequestDelegate _next = next ?? throw new ArgumentNullException(nameof(next));
+    private readonly FeatureMetricOptions _options = options.Value;
 
     public async Task InvokeAsync(HttpContext context)
     {
+        // Skip feature metric tracking for health check endpoints
+        if (ShouldSkipFeatureMetrics(context))
+        {
+            await _next(context);
+            return;
+        }
+
         // TODO: Analyze token to extract user and org info for feature metrics - do not log SSNs
         var deliveryContext = context.RequestServices.GetRequiredService<IFeatureMetricDeliveryContext>();
         try
@@ -34,6 +43,18 @@ public async Task InvokeAsync(HttpContext context)
 
     private static bool IsSuccessStatusCode(int statusCode) => statusCode is >= 200 and < 300;
 
+    private bool ShouldSkipFeatureMetrics(HttpContext context)
+    {
+        var path = context.Request.Path.Value;
+        if (string.IsNullOrEmpty(path))
+        {
+            return false;
+        }
+
+        return _options.ExcludedPathPrefixes.Any(excludedPath =>
+            path.StartsWith(excludedPath, StringComparison.OrdinalIgnoreCase));
+    }
+
     private static string GeneratePresentationTag(HttpContext context)
     {
         var method = context.Request.Method;

src/Digdir.Domain.Dialogporten.WebApi/Common/FeatureMetric/FeatureMetricOptions.cs

@@ -0,0 +1,18 @@
+namespace Digdir.Domain.Dialogporten.WebApi.Common.FeatureMetric;
+
+/// <summary>
+/// Configuration options for feature metric tracking.
+/// </summary>
+public sealed class FeatureMetricOptions
+{
+    /// <summary>
+    /// Gets or sets the list of path prefixes to exclude from feature metric tracking.
+    /// </summary>
+    public List<string> ExcludedPathPrefixes { get; set; } = new()
+    {
+        "/health",
+        "/metrics",
+        "/swagger",
+        "/openapi"
+    };
+}

src/Digdir.Domain.Dialogporten.WebApi/Program.cs

@@ -96,6 +96,7 @@ static void BuildAndRun(string[] args)
                 .AddAspNetCoreInstrumentationExcludingHealthPaths())
         // Options setup
         .ConfigureOptions<AuthorizationOptionsSetup>()
+        .Configure<FeatureMetricOptions>(builder.Configuration.GetSection("FeatureMetrics"))
 
         // Clean architecture projects
         .AddApplication(builder.Configuration, builder.Environment)