Implements inline type metadata emission in the source generator, matching runtime TypeMetadataBase. Computes FNV-1a hashes for type and property names, stores them in generated code, and emits metadata when UseMetadata is enabled. Adds per-type slot allocation and tracking for first/repeated metadata writes. Removes runtime fallback for UseMetadata, ensuring all logic is handled inline. Updates property filtering/order to match runtime, and optimizes Int32/Int64 skip logic. Thread-safe slot allocation is used for metadata tracking.