turbo

a4564683 - chore: Extract `turborepo-engine` crate from `turborepo-lib` (#11315)

chore: Extract `turborepo-engine` crate from `turborepo-lib` (#11315) ## Description Extract core Engine types into new `turborepo-engine` crate. **Moved to turborepo-engine:** - `Engine<S, T>` struct (generic over task definition) - `TaskNode`, `Building`, `Built`, `Error` - `execute.rs` - task execution logic - `dot.rs`, `mermaid.rs` - graph visualization **Kept in turborepo-lib:** - `builder.rs` - coupled to TurboJsonLoader - `task_inheritance.rs` - coupled to TurboJsonLoader - `ValidateError`, `validate()` - uses UIMode **Key design:** - `TaskDefinitionInfo` trait abstracts task definition fields engine needs - Type alias `Engine<S> = turborepo_engine::Engine<S, TaskDefinition>` for backward compat - `EngineExt` trait for lib-specific methods ## Testing instructions CI should pass, of course. I've also hand-tested this and I don't see anything strange happening.