feat(tvix/compiler): implement || operator

Same dance as `&&` but logically inverted.

Change-Id: I213e200e3836527e9abe510f354ee7cd1f70d041
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6151
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>

tvix/eval/src/opcode.rs

@@ -39,6 +39,7 @@ pub enum OpCode {
 
     // Logical operators & generic jumps
     OpJump(usize),
+    OpJumpIfTrue(usize),
     OpJumpIfFalse(usize),
 
     // Attribute sets