Add is_nested=False

[Fuzzkatt]

Attempt to fix #287

[Fuzzkatt]

cc @mruberry: Following your suggestion #93 (comment) that you linked in the original issue, I found out how to do the first half of the suggestion setting is_nested to always False. Could you review and add some suggestions on how to add the second half (ensuring that programs using nestedtensors always fail)?

[mruberry]

This is great, @Fuzzkatt, and I think we can stop this PR here. It does exactly what it should. Failing when provided with a nested tensor can be a separate issue (and should maybe be checked in the prologue, fyi @t-vi).

Would you add a test for this property, following the pattern here:

lightning-thunder/thunder/tests/opinfos.py

Line 548 in 843b2c2

tensor_properties: list[OpInfo] = []

and then let's merge this!

[mruberry]

Cool! Let's see if this unblocks operators that were testing for is_nested.

@Borda and @t-vi to merge

[mruberry]

@Fuzzkatt Looks like this picked up some conflicts that need to be resolved before it's merged

[mruberry]

@t-vi this needs to be merged manually because of flaky ci

[t-vi]

@Fuzzkatt @mruberry Thank you. Could you please resolve the merge conflicts? I'll check for CI issues and override as eneded.