Fix analyzer missing BuildHost method in multiple overloads detection (#158)

* Initial plan

* Add BuildHost method to analyzer's AnalyzeOverride checks and add test

Co-authored-by: pengweiqhca <[email protected]>

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: pengweiqhca <[email protected]>

Author: Copilot

src/Xunit.DependencyInjection.Analyzer/XunitDependencyInjectionAnalyzer.cs

@@ -124,6 +124,7 @@ private void AnalyzeSymbol(SymbolAnalysisContext context)
                     AnalyzeOverride(context, type, "ConfigureHost");
                     AnalyzeOverride(context, type, "ConfigureServices");
                     AnalyzeOverride(context, type, "Configure");
+                    AnalyzeOverride(context, type, "BuildHost");
                     AnalyzeOverride(context, type, "CreateHostApplicationBuilder");
                     AnalyzeOverride(context, type, "ConfigureHostApplicationBuilder");
                     AnalyzeOverride(context, type, "BuildHostApplicationBuilder");

test/Xunit.DependencyInjection.Analyzer.Test/DependencyInjectionTest.cs

@@ -151,6 +151,14 @@ await File.ReadAllTextAsync(Path.Combine("Startup", fixedSource), cancellationTo
             }
         ];
         yield return ["BuildHostTestStartup1.cs", null, Array.Empty<DiagnosticResult>()];
+        yield return
+        [
+            "BuildHostMultipleOverloadsTest.cs", null, new[]
+            {
+                new DiagnosticResult(Rules.MultipleOverloads).WithSpan(7, 21, 7, 30).WithArguments("BuildHost"),
+                new DiagnosticResult(Rules.MultipleOverloads).WithSpan(10, 21, 10, 30).WithArguments("BuildHost")
+            }
+        ];
 
         // CreateHostApplicationBuilder tests
         yield return

test/Xunit.DependencyInjection.Analyzer.Test/Startup/BuildHostMultipleOverloadsTest.cs

@@ -0,0 +1,12 @@
+using Microsoft.Extensions.Hosting;
+
+namespace TestProject
+{
+    public class Startup
+    {
+        public IHost BuildHost(IHostBuilder builder) => builder.Build();
+        
+        // This should trigger MultipleOverloads warning with the fix
+        public IHost BuildHost(IHostBuilder builder, string extra) => builder.Build();
+    }
+}