Add runtime API redesign scaffold

unshell-runtime/src/node/mod.rs

@@ -0,0 +1,73 @@
+//! Node-level runtime identity types.
+//!
+//! A node is the local runtime owner for protocol state, leaf bindings, and
+//! transport connections. This module only models identity and lifecycle state.
+
+pub mod packet;
+pub mod runtime;
+pub mod state;
+
+pub use packet::{EndpointState, PacketProcessor};
+pub use runtime::{NodeRuntime, NodeRuntimeError, TickBudget, TickOutcome};
+pub use state::NodeState;
+
+use crate::alloc::string::String;
+
+/// Stable identifier for a runtime node.
+#[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub struct NodeId(String);
+
+impl NodeId {
+    /// Creates a node identifier from an owned string.
+    #[must_use]
+    pub const fn new(value: String) -> Self {
+        Self(value)
+    }
+
+    /// Returns the identifier as a string slice.
+    #[must_use]
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+
+    /// Consumes the identifier and returns the owned string.
+    #[must_use]
+    pub fn into_string(self) -> String {
+        self.0
+    }
+}
+
+/// Minimal runtime node descriptor.
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct Node {
+    id: NodeId,
+    state: NodeState,
+}
+
+impl Node {
+    /// Creates a new node descriptor in the default [`NodeState::Created`] state.
+    #[must_use]
+    pub const fn new(id: NodeId) -> Self {
+        Self {
+            id,
+            state: NodeState::Created,
+        }
+    }
+
+    /// Returns the node identifier.
+    #[must_use]
+    pub const fn id(&self) -> &NodeId {
+        &self.id
+    }
+
+    /// Returns the current node lifecycle state.
+    #[must_use]
+    pub const fn state(&self) -> NodeState {
+        self.state
+    }
+
+    /// Updates the current node lifecycle state.
+    pub const fn set_state(&mut self, state: NodeState) {
+        self.state = state;
+    }
+}