feat: simplified mcp decorator

[hallvictoria]

Simplifies the mcp_tool_trigger decorator.

Customers can define MCP tools by adding the mcp_tool decorator - the arguments and tool properties are inferred based on the method definition.

@app.mcp_tool()
@app.blob_output(arg_name="file", connection="AzureWebJobsStorage", path=_BLOB_PATH)
def save_snippet(file: func.Out[str],
                 snippetname: str,
                 snippet: Optional[List[int]] = None) -> str:
    """Save a snippet to Azure Blob Storage."""
    file.set(snippet)
    logging.info(f"Saved snippet: {snippetname}")
    return f"Snippet '{snippetname}' saved successfully with content: {snippet}"

Alternatively, customers have the option to specify each tool property by using the mcp_tool_property decorator.

@app.mcp_tool()
@app.mcp_tool_property(arg_name="snippetname", description="The name of the snippet.")
@app.blob_output(arg_name="file", connection="AzureWebJobsStorage", path=_BLOB_PATH)
def save_snippet(file: func.Out[str],
                 snippetname: str,
                 snippet: Optional[List[int]] = None) -> str:
    """Save a snippet to Azure Blob Storage."""
    file.set(snippet)
    logging.info(f"Saved snippet: {snippetname}")
    return f"Snippet '{snippetname}' saved successfully with content: {snippet}"