Fix RootManifestReferencedTypes: remove IO, add relative name resolution

- Remove file-path overload (IO belongs in MSBuild task, not generator)
- Accept XDocument? directly, handle null with pattern match
- Add ResolveManifestClassName to resolve dot-relative (.MyActivity)
  and simple (MyService) names against the manifest package attribute
- Fix '$' handling in peer lookup: manifests use '$' for nested types,
  don't replace it with '.' in the lookup key

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: simonrozsival

src/Microsoft.Android.Sdk.TrimmableTypeMap/TrimmableTypeMapGenerator.cs

@@ -40,7 +40,7 @@ public TrimmableTypeMapResult Execute (
 			return new TrimmableTypeMapResult ([], [], allPeers);
 		}
 
-		RootManifestReferencedTypes (allPeers, manifestTemplatePath);
+		RootManifestReferencedTypes (allPeers, manifestTemplate);
 
 		var generatedAssemblies = GenerateTypeMapAssemblies (allPeers, systemRuntimeVersion);
 		var jcwPeers = allPeers.Where (p =>
@@ -144,32 +144,15 @@ List<GeneratedJavaSource> GenerateJcwJavaSources (List<JavaPeerInfo> allPeers)
 		return sources.ToList ();
 	}
 
-	void RootManifestReferencedTypes (List<JavaPeerInfo> allPeers, string? manifestTemplatePath)
+	internal void RootManifestReferencedTypes (List<JavaPeerInfo> allPeers, XDocument? doc)
 	{
-		if (manifestTemplatePath.IsNullOrEmpty () || !File.Exists (manifestTemplatePath)) {
-			return;
-		}
-
-		XDocument doc;
-		try {
-			doc = XDocument.Load (manifestTemplatePath);
-		} catch (Exception ex) {
-			warn?.Invoke ($"Failed to parse ManifestTemplate '{manifestTemplatePath}': {ex.Message}");
-			return;
-		}
-
-		RootManifestReferencedTypes (allPeers, doc);
-	}
-
-	internal void RootManifestReferencedTypes (List<JavaPeerInfo> allPeers, XDocument doc)
-	{
-		var root = doc.Root;
-		if (root is null) {
+		if (doc?.Root is not { } root) {
 			return;
 		}
 
 		XNamespace androidNs = "http://schemas.android.com/apk/res/android";
 		XName attName = androidNs + "name";
+		var packageName = (string?) root.Attribute ("package") ?? "";
 
 		var componentNames = new HashSet<string> (StringComparer.Ordinal);
 		foreach (var element in root.Descendants ()) {
@@ -180,7 +163,7 @@ internal void RootManifestReferencedTypes (List<JavaPeerInfo> allPeers, XDocumen
 			case "provider":
 				var name = (string?) element.Attribute (attName);
 				if (name is not null) {
-					componentNames.Add (name);
+					componentNames.Add (ResolveManifestClassName (name, packageName));
 				}
 				break;
 			}
@@ -190,9 +173,10 @@ internal void RootManifestReferencedTypes (List<JavaPeerInfo> allPeers, XDocumen
 			return;
 		}
 
+		// Build lookup by dot-name, keeping '$' for nested types (manifests use '$' too).
 		var peersByDotName = new Dictionary<string, List<JavaPeerInfo>> (StringComparer.Ordinal);
 		foreach (var peer in allPeers) {
-			var dotName = peer.JavaName.Replace ('/', '.').Replace ('$', '.');
+			var dotName = peer.JavaName.Replace ('/', '.');
 			if (!peersByDotName.TryGetValue (dotName, out var list)) {
 				list = [];
 				peersByDotName [dotName] = list;
@@ -213,4 +197,22 @@ internal void RootManifestReferencedTypes (List<JavaPeerInfo> allPeers, XDocumen
 			}
 		}
 	}
+
+	/// <summary>
+	/// Resolves an android:name value to a fully-qualified class name.
+	/// Names starting with '.' are relative to the package. Names with no '.' at all
+	/// are also treated as relative (Android tooling convention).
+	/// </summary>
+	static string ResolveManifestClassName (string name, string packageName)
+	{
+		if (name.StartsWith (".", StringComparison.Ordinal)) {
+			return packageName + name;
+		}
+
+		if (name.IndexOf ('.') < 0 && !packageName.IsNullOrEmpty ()) {
+			return packageName + "." + name;
+		}
+
+		return name;
+	}
 }