Assembly names containing dashes (e.g., tunit50-test) were causing compilation errors when using [Before(Assembly)] attributes due to invalid C# variable names being generated in the source code.

Problem

The source generator was only sanitizing dots (.) but not dashes (-) when creating C# variable names from assembly names. This resulted in invalid generated code like:

var tunit50-test_assembly = typeof(SomeType).Assembly;  // Invalid C# identifier

Which caused compilation errors:

error CS1002: ; expected
error CS0818: Implicitly-typed variables must be initialized
error CS0103: The name 'test_assembly' does not exist in the current context

Solution

Added .Replace("-", "_") to the existing sanitization chains in HookMetadataGenerator.cs at two key locations:

1. Line 470: Assembly variable declaration in GenerateStaticConstructor
2. Line 767: Assembly variable construction in GenerateAssemblyHookListPopulation

Now assembly names are properly sanitized to generate valid C# identifiers:

var tunit50_test_assembly = typeof(SomeType).Assembly;  // Valid C# identifier

Testing

• ✅ All existing source generator tests pass (178 succeeded, 0 failed)
• ✅ Public API tests confirm no breaking changes (6 succeeded, 0 failed)
• ✅ Manual verification with test project using assembly name test-assembly-with-dashes
• ✅ Added integration test to document the fix

The changes are minimal and surgical, following the existing pattern used elsewhere in the codebase for sanitizing names (e.g., in DataSourceHelpersGenerator.cs).

Fixes #2919.

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