Add notes regarding label usage, provided by i18n review

A suggested by @xfq, add additional details about operator labels,
clarifying that they are not intended to be natural language strings.
And include an advisement that use of developer-provided labels is
subject to spoofing, and implementations should sanitize them.

Author: inexorabletash

index.bs

@@ -701,8 +701,12 @@ A key part of the {{MLGraphBuilder}} interface are methods such as {{MLGraphBuil
 
 An [=operator=] has a <dfn for=operator>label</dfn>, a string which may be included in diagnostics such as [=exception=] messages. When an [=operator=] is created its [=operator/label=] is initialized in an [=implementation-defined=] manner and may include the passed {{MLOperatorOptions/label}}.
 
+Note: The label is not intended to be a natural language string. It is a language-independent identifier, analogous to a variable name or error code, like `"mul#1234"`.
+
 Note: Implementations are encouraged to use the {{MLOperatorOptions/label}} provided by developers to enhance error messages and improve debuggability, including both synchronous errors during graph construction and for errors that occur during the asynchronous {{MLGraphBuilder/build()}} method.
 
+Advisement: When displaying labels provided by developers via {{MLOperatorOptions/label}} in debugging tools, logs, or error messages, implementations should sanitize the output to prevent security risks, such as injection of malicious Unicode sequences (e.g., bidirectional control characters as described in Unicode Technical Report #36, Trojan Source attacks). For example, implementations should escape or filter control characters (e.g., U+202A to U+202E, U+2066 to U+2069) or use a safe rendering mechanism to neutralize potential spoofing.
+
 ISSUE(778): Consider adding a mechanism for reporting errors during {{MLContext/dispatch()}}.
 
 At inference time, every {{MLOperand}} will be bound to a tensor (the actual data), which are essentially multidimensional arrays. The representation of the tensors is implementation dependent, but it typically includes the array data stored in some buffer (memory) and some metadata describing the array data (such as its shape).