Language Server should notice loop nesting

[vbar]

Current hooks-guard-in-for clang-tidy check only looks at for loops in isolation. It should also take into account their nesting, so that when it proposes to insert a call to _g, it computes its second argument not just as this loop iterations + 1, but as (this loop iterations + 1) * (each parent loop's iteration's), e.g.

uint8_t acc[20];

for (int i = 0; _g(__LINE__, 11), i < 10; ++i)
{
    for (int j = 0; _g(__LINE__, 30), j < 2; ++j)
    {
        for (int k = 0; _g(__LINE__, 120),  k < 5; ++k)
        {
            hook_account(acc, 20);
        }
        for (int k = 0; _g(__LINE__, 120),  k < 5; ++k)
        {
            hook_account(acc, 20);
        }
    }
}

while also recognizing when the computation cannot be done (e.g. when the loops have dynamic limits).