feat: Ternary operator support in simple non-comptime cases

[iwoplaza]

If we can ensure that both branches of a ternary operator are side-effect free with heuristics, we can emit a select() call instead.

Maybe the heuristic essentially boils down to "Is there a call expression in here?"

Note

We can also do proper side-effect analysis to allow side-effect free functions to be used in ternary operators. We can store this as another kind of flag on the snippet type.

If there are more cases where this sort of analysis might be useful, we can prioritize this.

[aleksanderkatan]

nit regarding our GitHub workflow: I don't like how now every new issue gets added to the same milestone, even if it requires further research and its scope is not measured yet (and also the fact that this milestone is named 0.11.5 when we released 0.11.6 already). I think that the idea behind milestones is that they should be achievable, and that's the reason why they display the completion percentage. Can we use the priority system instead, and only include must-haves in version milestones?