Fix #15086 syntaxError for ternary with two inequalities

[chrchr-github]

No description provided.

[danmar]

This is an AI review take it with a grain of salt. Please feel free to reject it by clicking on Resolve button

Verdict: the logic looks correct to me. An unmatched : cannot appear in valid template arguments, so returning 0 there only makes template detection stricter and should not introduce false positives. Real ternary template arguments still work (existing tests cover std::array<int, B ? 1 : 2> and nested ternaries), parenthesized ternaries are skipped via the link, and :: is a separate token so it is not affected. I built the branch locally and TestSimplifyTemplate, TestTokenizer, TestSimplifyTypedef, TestVarID and TestGarbage pass (1321 tests, 0 failed). The inline comments are only style/naming nits.

The PR title still says #15XXX; please replace it with the actual trac ticket number.

[chrchr-github]

Needs to handle

template <typename T, typename U>
bool f(U u, bool b) {
  return u.template operator()<T>() || b;
}