Bind selected capability roots to model steps

codex-rs/exec-server/src/resolved_capability.rs

@@ -0,0 +1,47 @@
+use std::fmt;
+use std::sync::Arc;
+
+use codex_protocol::capabilities::SelectedCapabilityRoot;
+
+use crate::Environment;
+use crate::ExecutorFileSystem;
+
+/// A selected capability root pinned to the exact environment instance that owns it.
+///
+/// This value is process-local and must not be persisted. Cloning it keeps the same
+/// [`Environment`] alive so every consumer of one model step uses the same executor.
+#[derive(Clone)]
+pub struct ResolvedSelectedCapabilityRoot {
+    selected_root: SelectedCapabilityRoot,
+    environment: Arc<Environment>,
+}
+
+impl ResolvedSelectedCapabilityRoot {
+    pub fn new(selected_root: SelectedCapabilityRoot, environment: Arc<Environment>) -> Self {
+        Self {
+            selected_root,
+            environment,
+        }
+    }
+
+    pub fn selected_root(&self) -> &SelectedCapabilityRoot {
+        &self.selected_root
+    }
+
+    pub fn environment(&self) -> &Arc<Environment> {
+        &self.environment
+    }
+
+    pub fn file_system(&self) -> Arc<dyn ExecutorFileSystem> {
+        self.environment.get_filesystem()
+    }
+}
+
+impl fmt::Debug for ResolvedSelectedCapabilityRoot {
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+        formatter
+            .debug_struct("ResolvedSelectedCapabilityRoot")
+            .field("selected_root", &self.selected_root)
+            .finish_non_exhaustive()
+    }
+}