Use Roslyn to make sure all objects inherited from EventBase and StateBase have the [GenerateSerializer] attribute

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User Story
As a developer, I want a Roslyn analyzer that ensures every class inheriting from EventBase or StateBase is decorated with the [GenerateSerializer] attribute, so that serialization code is always generated correctly and missing attributes are caught at compile time.

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Details & Requirements

1. Analyzer Implementation

   • Use the Roslyn CompilationStartAction to register a syntax node action for ClassDeclarationSyntax.
   • For each class, use semantic analysis to check if its base type is EventBase or StateBase (directly or indirectly). :contentReference[oaicite:0]{index=0}
   • If such a class lacks the [GenerateSerializer] attribute, report a diagnostic with an error severity.

2. Code Fix Provider

   • Provide a code-fix that adds the [GenerateSerializer] attribute to the class declaration when the diagnostic is triggered.
   • Ensure the fix respects existing using directives or adds using Orleans.CodeGeneration; as needed.

3. Configuration & Suppression

   • Allow users to suppress the diagnostic via #pragma or EditorConfig settings if there are valid exceptions.
   • Expose a rule ID (e.g., AGENT001) and description in the analyzer’s descriptor for easy configuration.

4. Testing & Integration

   • Create unit tests using the Roslyn test framework to verify detection on classes inheriting from EventBase/StateBase with and without the attribute.
   • Include integration tests to ensure the analyzer and code-fix work in real projects under the CI pipeline.

5. Documentation & Adoption

   • Document how to install and enable the analyzer in project files (e.g., via NuGet).
   • Provide examples of classes that will pass or fail the check, and guide on how to apply the code fix.

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Acceptance Criteria

• The analyzer reports an error for each class deriving from EventBase or StateBase that does not have [GenerateSerializer].
• The provided code fix correctly adds the attribute and required using directive.
• Tests cover direct and indirect inheritance scenarios, as well as suppression cases.
• Documentation is available detailing rule ID, configuration options, and usage examples.