feat(aot): add VerifyReferenceAotCompatibility option

When EnableAotTesting=true, consumers can opt-in to verify all
referenced assemblies are marked as AOT-compatible. This triggers
IL3058 warnings for dependencies without IsAotCompatible metadata.

Usage:
<PropertyGroup>
  <EnableAotTesting>true</EnableAotTesting>
  <VerifyReferenceAotCompatibility>true</VerifyReferenceAotCompatibility>
</PropertyGroup>

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: ANcpLua

src/Testing/AotTesting/AotTesting.props

@@ -22,6 +22,17 @@
     <DefaultAotTestTimeout Condition="'$(DefaultAotTestTimeout)' == ''">300</DefaultAotTestTimeout>
   </PropertyGroup>
 
+  <!--
+    AOT Compatibility Verification
+
+    When enabled, verifies that all referenced assemblies are marked as AOT-compatible.
+    This triggers IL3058 warnings for dependencies without IsAotCompatible metadata.
+    Opt-in to catch unmarked but potentially incompatible dependencies early.
+  -->
+  <PropertyGroup Condition="'$(EnableAotTesting)' == 'true'">
+    <VerifyReferenceAotCompatibility Condition="'$(VerifyReferenceAotCompatibility)' == ''">false</VerifyReferenceAotCompatibility>
+  </PropertyGroup>
+
   <!--
     AOT Testing Package References