manager: add update_meta_inputs tool to update flake.lock on demand (closes #235)

hive-sh4re/src/lib.rs

@@ -842,6 +842,17 @@ pub enum ManagerRequest {
     /// message into the manager's own broker inbox. `from` is caller-
     /// chosen; `body` becomes the wake prompt body.
     Wake { from: String, body: String },
+    /// Run `nix flake update [inputs...]` on the meta flake and commit
+    /// the resulting `flake.lock` changes. `inputs` is the list of
+    /// named inputs to update (e.g. `["bitburner-agent", "nixpkgs"]`).
+    /// Pass an empty list to update ALL inputs (equivalent to bare
+    /// `nix flake update`). Blocks until the lock step completes;
+    /// does NOT trigger a rebuild — call `update` on each affected
+    /// agent separately after the lock settles.
+    UpdateMetaInputs {
+        #[serde(default)]
+        inputs: Vec<String>,
+    },
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]