chore: rename executor -> evaluator and integrate into app

crates/app/src/config/cli.rs

@@ -4,6 +4,14 @@ use clap::{builder::BoolishValueParser, ArgAction, Parser};
 
 #[derive(Parser)]
 pub(crate) struct Args {
+    /// What file contains the pipeline to evaluate.
+    pub source: PathBuf,
+
+    /// How to actually run the pipeline.
+    /// Overrides the config file. Defaults to the debug evaluator.
+    #[arg(short, long)]
+    pub evaluator: Option<eval::Available>,
+
     /// Read this config file.
     #[arg(short, long)]
     pub config_path: Option<PathBuf>,