Add more test cases for recursion

[davidhewitt]

I will be candid: I asked Claude to examine cases that are probably not covered by recursion defences, it immediately found two more test cases which both blow the stack.

Committing these first and then can work towards fixing.

[codspeed-hq]

Merging this PR will not alter performance

✅ 13 untouched benchmarks

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_{Comparing dh/more-recursion-guard (7f913e4) with main (d634706)}