Add feature-usage tracking and dashboard charts

Instruments FeatureEvaluationService with System.Diagnostics.Metrics (Counter + IMeterFactory). Accumulates per-feature/day evaluation counts in-process, flushed every 30s to a new FeatureUsageDaily Postgres table via PostgreSQL ON CONFLICT upsert. Caches dashboard query results for 180s in IMemoryCache. New GET /api/v1/environments/{id}/usage endpoint returns top-10 features last day and 14-day per-day breakdown. Admin dashboard shows two ApexCharts bar charts: top features and evaluations by day with per-flag hover tooltip.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

CLAUDE.md

@@ -24,10 +24,17 @@ MicCheck: open source. asp.net, c#, typescript, VueJS. Manages feature flags, pr
 # Coding
 - Descriptive names for all classes/methods. No generic names: Provider, Manager, Helper
 - Match formatting/style from `.editorconfig`
+- Wrap lines at 220 characters, leave single line if fewer
+- Place interfaces that are implemented by a single class at the bottom of the class file.  An interface with multiple implementations of an interface should be in a seperate file.
+- Do not use tuples for return types.  Prefer records or classes for multiple values
+- Do not use `sealed` on classes- 
+- Use `record` for data objects, `class` for objects with behavior. Avoid mutable state where possible.
 
 ## Testing
 - BDD-style unit tests, end-to-end as possible, no external resources (DB, filesystem). e.g. `WhenAUserDoesSomething_ThenAThingAppears`
 - Mock external deps with Moq
+- New features need unit tests covering as much logic as possible
+- Any modified file: evaluate for missing test coverage- 
 - No "Mock" in mocked object names
 - No Arrange/Act/Assert comments
 

src/MicCheck.AppHost/AppHost.cs

@@ -0,0 +1,14 @@
+var builder = DistributedApplication.CreateBuilder(args);
+
+var postgres = builder.AddPostgres("postgres").WithDataVolume("miccheck-pgdata").WithPgAdmin();
+
+var miccheckDb = postgres.AddDatabase("miccheck");
+
+var api = builder.AddProject<Projects.MicCheck_Api>("api").WithReference(miccheckDb).WaitFor(miccheckDb);
+
+builder.AddViteApp("admin", "../admin", "serve")
+    .WithReference(api)
+    .WaitFor(api)
+    .WithExternalHttpEndpoints();
+
+builder.Build().Run();

src/MicCheck.AppHost/MicCheck.AppHost.csproj

@@ -0,0 +1,23 @@
+<Project Sdk="Aspire.AppHost.Sdk/13.4.0">
+
+  <ItemGroup>
+    <ProjectReference Include="..\api\MicCheck.Api\MicCheck.Api.csproj" />
+    <ProjectReference Include="..\admin\Admin.esproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Aspire.Hosting.JavaScript" Version="13.4.2" />
+    <PackageReference Include="Aspire.Hosting.PostgreSQL" Version="13.4.0" />
+  </ItemGroup>
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <LangVersion>latest</LangVersion>
+    <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <UserSecretsId>d10a4485-2ac0-4ba7-bda5-8eb63e417567</UserSecretsId>
+  </PropertyGroup>
+
+</Project>

src/MicCheck.AppHost/Properties/launchSettings.json

@@ -0,0 +1,29 @@
+{
+  "$schema": "https://json.schemastore.org/launchsettings.json",
+  "profiles": {
+    "https": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "applicationUrl": "https://localhost:17244;http://localhost:15050",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development",
+        "DOTNET_ENVIRONMENT": "Development",
+        "ASPIRE_DASHBOARD_OTLP_ENDPOINT_URL": "https://localhost:21229",
+        "ASPIRE_RESOURCE_SERVICE_ENDPOINT_URL": "https://localhost:22051"
+      }
+    },
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "applicationUrl": "http://localhost:15050",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development",
+        "DOTNET_ENVIRONMENT": "Development",
+        "ASPIRE_DASHBOARD_OTLP_ENDPOINT_URL": "http://localhost:19033",
+        "ASPIRE_RESOURCE_SERVICE_ENDPOINT_URL": "http://localhost:20209"
+      }
+    }
+  }
+}

src/MicCheck.AppHost/appsettings.Development.json

@@ -0,0 +1,16 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "Dashboard": {
+    "Frontend": {
+      "AuthMode": "Unsecured"
+    },
+    "Otlp": {
+      "AuthMode": "Unsecured"
+    }
+  }
+}

src/MicCheck.AppHost/appsettings.json

@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning",
+      "Aspire.Hosting.Dcp": "Warning"
+    }
+  }
+}

src/MicCheck.AppHost/aspire.config.json

@@ -0,0 +1,5 @@
+{
+  "appHost": {
+    "path": "MicCheck.AppHost.csproj"
+  }
+}

src/MicCheck.ServiceDefaults/Extensions.cs

@@ -0,0 +1,127 @@
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Diagnostics.HealthChecks;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.ServiceDiscovery;
+using OpenTelemetry;
+using OpenTelemetry.Metrics;
+using OpenTelemetry.Trace;
+
+namespace Microsoft.Extensions.Hosting;
+
+// Adds common Aspire services: service discovery, resilience, health checks, and OpenTelemetry.
+// This project should be referenced by each service project in your solution.
+// To learn more about using this project, see https://aka.ms/aspire/service-defaults
+public static class Extensions
+{
+    private const string HealthEndpointPath = "/health";
+    private const string AlivenessEndpointPath = "/alive";
+
+    public static TBuilder AddServiceDefaults<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
+    {
+        builder.ConfigureOpenTelemetry();
+
+        builder.AddDefaultHealthChecks();
+
+        builder.Services.AddServiceDiscovery();
+
+        builder.Services.ConfigureHttpClientDefaults(http =>
+        {
+            // Turn on resilience by default
+            http.AddStandardResilienceHandler();
+
+            // Turn on service discovery by default
+            http.AddServiceDiscovery();
+        });
+
+        // Uncomment the following to restrict the allowed schemes for service discovery.
+        // builder.Services.Configure<ServiceDiscoveryOptions>(options =>
+        // {
+        //     options.AllowedSchemes = ["https"];
+        // });
+
+        return builder;
+    }
+
+    public static TBuilder ConfigureOpenTelemetry<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
+    {
+        builder.Logging.AddOpenTelemetry(logging =>
+        {
+            logging.IncludeFormattedMessage = true;
+            logging.IncludeScopes = true;
+        });
+
+        builder.Services.AddOpenTelemetry()
+            .WithMetrics(metrics =>
+            {
+                metrics.AddAspNetCoreInstrumentation()
+                    .AddHttpClientInstrumentation()
+                    .AddRuntimeInstrumentation();
+            })
+            .WithTracing(tracing =>
+            {
+                tracing.AddSource(builder.Environment.ApplicationName)
+                    .AddAspNetCoreInstrumentation(tracing =>
+                        // Exclude health check requests from tracing
+                        tracing.Filter = context =>
+                            !context.Request.Path.StartsWithSegments(HealthEndpointPath)
+                            && !context.Request.Path.StartsWithSegments(AlivenessEndpointPath)
+                    )
+                    // Uncomment the following line to enable gRPC instrumentation (requires the OpenTelemetry.Instrumentation.GrpcNetClient package)
+                    //.AddGrpcClientInstrumentation()
+                    .AddHttpClientInstrumentation();
+            });
+
+        builder.AddOpenTelemetryExporters();
+
+        return builder;
+    }
+
+    private static TBuilder AddOpenTelemetryExporters<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
+    {
+        var useOtlpExporter = !string.IsNullOrWhiteSpace(builder.Configuration["OTEL_EXPORTER_OTLP_ENDPOINT"]);
+
+        if (useOtlpExporter)
+        {
+            builder.Services.AddOpenTelemetry().UseOtlpExporter();
+        }
+
+        // Uncomment the following lines to enable the Azure Monitor exporter (requires the Azure.Monitor.OpenTelemetry.AspNetCore package)
+        //if (!string.IsNullOrEmpty(builder.Configuration["APPLICATIONINSIGHTS_CONNECTION_STRING"]))
+        //{
+        //    builder.Services.AddOpenTelemetry()
+        //       .UseAzureMonitor();
+        //}
+
+        return builder;
+    }
+
+    public static TBuilder AddDefaultHealthChecks<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
+    {
+        builder.Services.AddHealthChecks()
+            // Add a default liveness check to ensure app is responsive
+            .AddCheck("self", () => HealthCheckResult.Healthy(), ["live"]);
+
+        return builder;
+    }
+
+    public static WebApplication MapDefaultEndpoints(this WebApplication app)
+    {
+        // Adding health checks endpoints to applications in non-development environments has security implications.
+        // See https://aka.ms/aspire/healthchecks for details before enabling these endpoints in non-development environments.
+        if (app.Environment.IsDevelopment())
+        {
+            // All health checks must pass for app to be considered ready to accept traffic after starting
+            app.MapHealthChecks(HealthEndpointPath);
+
+            // Only health checks tagged with the "live" tag must pass for app to be considered alive
+            app.MapHealthChecks(AlivenessEndpointPath, new HealthCheckOptions
+            {
+                Predicate = r => r.Tags.Contains("live")
+            });
+        }
+
+        return app;
+    }
+}

src/MicCheck.ServiceDefaults/MicCheck.ServiceDefaults.csproj

@@ -0,0 +1,24 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <LangVersion>latest</LangVersion>
+    <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <IsAspireSharedProject>true</IsAspireSharedProject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <FrameworkReference Include="Microsoft.AspNetCore.App" />
+
+    <PackageReference Include="Microsoft.Extensions.Http.Resilience" Version="10.6.0" />
+    <PackageReference Include="Microsoft.Extensions.ServiceDiscovery" Version="10.6.0" />
+    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.15.3" />
+    <PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.15.3" />
+    <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.15.2" />
+    <PackageReference Include="OpenTelemetry.Instrumentation.Http" Version="1.15.1" />
+    <PackageReference Include="OpenTelemetry.Instrumentation.Runtime" Version="1.15.1" />
+  </ItemGroup>
+
+</Project>

src/admin/Admin.esproj

@@ -0,0 +1,11 @@
+<Project Sdk="Microsoft.VisualStudio.JavaScript.Sdk/1.0.2752196">
+  <PropertyGroup>
+    <StartupCommand>npm run serve</StartupCommand>
+    <JavaScriptTestRoot>.\</JavaScriptTestRoot>
+    <JavaScriptTestFramework>Jest</JavaScriptTestFramework>
+    <!-- Allows the build (or compile) script located on package.json to run on Build -->
+    <ShouldRunBuildScript>false</ShouldRunBuildScript>
+    <!-- Folder where production build objects will be placed -->
+    <BuildOutputFolder>$(MSBuildProjectDirectory)\dist</BuildOutputFolder>
+  </PropertyGroup>
+</Project>

src/admin/package.json

@@ -14,10 +14,12 @@
     "@iconify-json/ri": "^1.2.0",
     "@iconify/vue": "^4.1.0",
     "@vueuse/core": "^11.0.0",
+    "apexcharts": "^5.15.0",
     "axios": "^1.15.0",
     "pinia": "^3.0.4",
     "vue": "^3.4.0",
     "vue-router": "^4.3.0",
+    "vue3-apexcharts": "^1.11.1",
     "vue3-perfect-scrollbar": "^2.0.0",
     "vuetify": "^3.7.5"
   },
@@ -31,6 +33,7 @@
     "@vue/test-utils": "^2.4.6",
     "@vue/vue3-jest": "^29.2.6",
     "babel-jest": "^29.7.0",
+    "eslint": "^10.4.1",
     "jest": "^29.7.0",
     "jest-environment-jsdom": "^29.7.0",
     "sass": "^1.77.2",