Use impl IntoIterator consistently

[logan-gatlin]

Use impl IntoIterator consistently in all APIs. This replaces two other patterns that were in use:

• Vec<T> parameters
• impl Into<Option<Vec<T>>>
  Using a Vec<T> parameter when only an iterable collection is an anti-pattern. Using IntoIterator instead allows users to pass arrays by value instead since the function is now generic over all array sizes (among many other types).

impl Into<Option<Vec<T>>> is also a poor practice. In every case where it was used, Some(vec![]) and None where treated the same, making the Option wrapper redundant. Since Option implements iterator, users passing None will see no change.

This change is not backwards compatible, but most users will have to make little to no change to existing code.

[codspeed-hq]

Merging this PR will not alter performance

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

✅ 2 untouched benchmarks

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_{Comparing logan/sql-api-cleanup (386c504) with main (2d022ab)}

[guybedford]

As a breaking change, I will leave this open to reconsider as part of a comprehensive redesign of the API rather than doing incremental breaks sporadically.