009 reject unparseable condition

// Template engine: a condition outside the `{% if %}` grammar is a LOUD compile
// error (KORU125), never a silent false. `and` is not in the grammar — a
// condition is a bare key, or two operands compared with `==` / `!=`.
//
// The wall is what makes the grammar honest. Without it the whole condition
// text was looked up as one variable NAME, missed, and rendered `{% else %}`
// every time: a guarded branch that reads as live while being unreachable, and
// unreachable no matter what a later author writes inside it. Any fix attempted
// in that branch is inert, which is exactly how it stays undiscovered.
~import std/io

~pub tor probe-bad { n: usize }

~proc probe-bad|template|zig {
    {% if n and n %}@import("std").debug.print("never\n", .{});{% endif %}
}

~probe-bad(n: 1)