fix(explicit_counter_loop): suggest .take(n) for for _ in 0..n co…

[zayutaha]

When a loop variable is unused (for _ in 0..n) and the counter is being
incremented, Clippy previously suggested the generic zip-based rewrite.
This PR adds a more idiomatic .take(n) suggestion for the common case
where the range is half-open and starts at zero:

// before
for _ in 0..MAX {
    base += 1;
}

// suggested
for base in (100..).take(MAX)

Non-zero starts (5..MAX) and inclusive ranges (0..=MAX) are
explicitly excluded and fall through to the existing zip suggestion.
Both cases are covered by new UI tests.

changelog: [explicit_counter_loop]: suggest (init..).take(n) when loop variable is unused and range is 0..n

fixes #16642

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[Jarcho]

Why is_none_or? RangeTo isn't iterable in the first place.

[zayutaha]

Thanks for the suggestion! The zero check is still needed though — without it, for _ in 5..MAX would incorrectly suggest (init..).take(MAX), which runs MAX times instead of the correct MAX - 5 times. I've added test cases for both non-zero start and inclusive ranges to cover this.