Weird, I tried looking up Construct definition and Construct traits for 5E, and got hints they're defined in the Monster Manual, but I'm AFB, so that didn't help me.

Seems since the SD is listed as a medium construct, that it would have all the standard abilities and immunities that all constructs share. Would make sense that 'eating, drinking, breathing' would be part of it. Of course, specific beats general, so the question is, are the condition and damage immunities listed on the SD stat block all inclusive, or additive... yeah, that'd be a DM ruling.