* fix: standardize error handling across handlers with MCP specification compliance
* Update mcp-elements.md
Co-authored-by: Christopher Hertel <mail@christopher-hertel.de>
* docs: clarify error handling behavior for all element types
* docs: remove unnecessary whitespace in mcp-elements.md
* fix: simplify exception signatures to accept simple messages
* refactor: use specific exceptions in examples for better error handling
* feat: throw exceptions from reference provider instead of returning null
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Co-authored-by: Christopher Hertel <mail@christopher-hertel.de>
