refactor(core): support tiered layer nodes (#33937)

packages/opencode/test/session/snapshot-tool-race.test.ts

@@ -84,14 +84,14 @@ const root = LayerNode.group([
   SessionSummary.node,
   Database.node,
   CrossSpawnSpawner.node,
-  LayerNode.make(TestLLMServer.layer, []),
+  LayerNode.make({ service: TestLLMServer, layer: TestLLMServer.layer, deps: [] }),
 ])
 const it = testEffect(
   LayerNode.buildLayer(root, {
     replacements: [
-      LayerNode.replace(MCP.node, mcp),
-      LayerNode.replace(LSP.node, lsp),
-      LayerNode.replace(RuntimeFlags.node, RuntimeFlags.layer({ experimentalEventSystem: true })),
+      LayerNode.replace(MCP.layer, mcp),
+      LayerNode.replace(LSP.layer, lsp),
+      LayerNode.replace(RuntimeFlags.defaultLayer, RuntimeFlags.layer({ experimentalEventSystem: true })),
     ],
   }),
 )