Runtime expression `name` rule inconsistent with path template grammar

[char0n]

The runtime expression ABNF grammar defines:

name = *( char )
token = 1*tchar

The * (zero or more) quantifier on name means expressions like $request.query. and $request.path. with empty names are syntactically valid per the grammar.

The OpenAPI spec states that the Parameter Object's name field is REQUIRED:

REQUIRED. The name of the parameter. Parameter names are case-sensitive.

A required field with an empty string value is arguably not meaningful, though the spec doesn't explicitly say "non-empty".

For path parameters specifically, this is inconsistent with the path template grammar introduced in OpenAPI 3.2.0:

template-expression-param-name = 1*( %x00-7A / %x7C / %x7E-10FFFF )

The 1* quantifier requires at least one character for path parameter names. So {userId} is valid but {} is not. Yet the runtime expression $request.path. (empty name) is accepted by the grammar.

For query parameters, the situation is less clear — HTTP technically allows empty query parameter keys (?=value), though this is extremely uncommon.

For consistency with the path template grammar and the token = 1*tchar rule (which already requires at least one character for headers), consider changing:

name = *( char )

to:

name = 1*( char )

This would require at least one character for query and path parameter names, aligning the runtime expression grammar with the path template grammar.