Added R code blocks, huge partion of tutorials covered -c

[cemdusenkalkan]

added total of 35 R code blocks,
I <3 C

[cemdusenkalkan]

@trivialfis any problems with the tests?

[trivialfis]

No issue there. It's a Java document test, not related to this PR. We are still looking into it.

[trivialfis]

Hi, did you try to verify the examples you or the LLM wrote? Asking because there's no enable_categorical in R.

[trivialfis]

Please verify the correctness of all examples.

[cemdusenkalkan]

Hi, did you try to verify the examples you or the LLM wrote? Asking because there's no enable_categorical in R.

#9810 --> maybe should comment them out, not implemented yet. Or I'll delete it, and keep this comment as a reminder

[cemdusenkalkan]

sliced out some of the incoming features of R package, didn't know they were not there since not using a lot in R

[trivialfis]

sliced out some of the incoming features of R package, didn't know they were not there since not using a lot in R

Hi, I think you can try to use the R package before writing examples for others. The features are in the latest package, but you need to figure out how to use them through the existing document and code before adding new examples to the document.