Add comprehensive analysis and decision summary for XML vs direct command approach

[cto-new]

Summary

This PR greatly extends the robustness of Vector's tool call parser and improves asset search reliability by supporting a broad range of XML and JSON-based tool call formats, including nested tags, attribute-based tags, comma-separated and array representations.

Details

• The XML/JSON hybrid parser for tool calls now recognizes and extracts arguments from native function-calling JSON, standard XML with child elements, single XML tags with attributes, repeated tags as arrays, comma-separated values, and mixed/nested structures.
• Asset search tags are extracted as arrays regardless of how the model emits them (array, string, CSV list, or nested XML).
• Introduces deep, defensive extraction helpers for both strings and arrays to minimize brittle parsing logic and maximize compatibility across model output variations.
• Improves error tolerance and validation to catch and report malformed or missing search parameters.
• Documentation and decision summary updated to reflect these enhancements with implementation notes and test cases.