Fixed XML response handling for entity-heavy NCBI payloads, preserved decoded Unicode metadata, and wrapped parser failures as SerializationError.
Adjusted NcbiService retry semantics so only transient McpError failures are retried.
Updated @cyanheads/mcp-ts-core to ^0.3.5 and fast-xml-parser to ^5.5.12, and added regression coverage for Unicode metadata, en-dash page ranges, parser failure wrapping, and entity-heavy XML payloads.