build: enable all .NET analyzers in every build (AnalysisMode=All)

.editorconfig

@@ -28,3 +28,13 @@ dotnet_diagnostic.CA1826.severity = none
 dotnet_diagnostic.CA2008.severity = none
 dotnet_diagnostic.CA1829.severity = none
 dotnet_diagnostic.CA2213.severity = none
+
+[{src/LageBuch.App.Android/*.cs,src/LageBuch.App.Android/**/*.cs}]
+# Java-managed objects (Intent, Java.IO.File, ActivityResultLauncher, ActivityResultContracts.*)
+# have their lifetime owned by the Android runtime: they must survive past the C# call that hands
+# them to the platform (StartActivity / RegisterForActivityResult), so "dispose" here would break
+# the OS callbacks. MimeTypeOf likewise deliberately produces lowercase MIME values, which
+# Intent.SetDataAndType expects — ToUpperInvariant (CA1308) would violate that contract.
+dotnet_diagnostic.CA1308.severity = none
+dotnet_diagnostic.CA2000.severity = none
+dotnet_diagnostic.CA2213.severity = none

Directory.Build.props

@@ -5,6 +5,7 @@
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <AnalysisMode>All</AnalysisMode>
     <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
     <!-- Required so IDE0005 (unused usings) runs during build; suppress the
          XML-doc-comment warnings that GenerateDocumentationFile turns on. -->

src/LageBuch.App.Android/MainActivity.cs

@@ -21,6 +21,11 @@ namespace LageBuch.App.Android;
     ConfigurationChanges = ConfigChanges.Orientation | ConfigChanges.ScreenSize | ConfigChanges.UiMode)]
 public class MainActivity : AvaloniaMainActivity<SharedApp>
 {
+    // OpenDocument (rather than GetContent) accepts multiple MIME types on Launch, needed
+    // since an attachment can be any of several image types or a PDF.
+    private static readonly string[] AttachmentMimeTypes =
+        ["image/jpeg", "image/png", "image/gif", "image/webp", "application/pdf"];
+
     private ActivityResultLauncher? _importLauncher;
     private ActivityResultLauncher? _attachmentLauncher;
     private AndroidFileDialogService? _dialogs;
@@ -51,8 +56,7 @@ protected override AppBuilder CustomizeAppBuilder(AppBuilder builder)
     {
         _dialogs = new AndroidFileDialogService(this);
         _dialogs.OnLaunchImportPicker = () => _importLauncher!.Launch("application/json");
-        _dialogs.OnLaunchAttachmentPicker = () => _attachmentLauncher!.Launch(
-            new[] { "image/jpeg", "image/png", "image/gif", "image/webp", "application/pdf" });
+        _dialogs.OnLaunchAttachmentPicker = () => _attachmentLauncher!.Launch(AttachmentMimeTypes);
         SharedApp.CreateMainViewModel = () => CompositionRoot.CreateMainWindowViewModel(
             new IncidentStore(),
             new MasterDataProvider(AndroidAppPaths.MasterDataDbPath(this)),