fix(actor): read lsp_binding from NodeDefinition field instead of config dict in compiler

The _extract_lsp_bindings() function now reads from the dedicated typed
node.lsp_binding (NodeLspBinding) field and converts it to LspBinding records.
Also maintains backward compatibility by checking the config dict for legacy
lsp_bindings configuration.

Fixes the issue where per-node LSP bindings configured via the lsp_binding:
YAML key were being silently ignored during actor graph compilation.

ISSUES CLOSED: #1432

src/cleveragents/actor/compiler.py

@@ -156,11 +156,36 @@ def _map_edge(edge: EdgeDefinition) -> lg_nodes.Edge:
 
 
 def _extract_lsp_bindings(node: NodeDefinition) -> list[LspBinding]:
-    """Extract LSP bindings from a node config block."""
+    """Extract LSP bindings from a node's dedicated lsp_binding field.
+    
+    Reads from the typed ``node.lsp_binding`` (NodeLspBinding) field and
+    converts to LspBinding records. Also checks config dict for backward
+    compatibility with legacy ``lsp_bindings`` config key.
+    
+    Args:
+        node: The node definition to extract bindings from.
+        
+    Returns:
+        List of LspBinding records for this node.
+    """
     bindings: list[LspBinding] = []
+    
+    # Primary path: read from the dedicated typed field (NodeLspBinding)
+    if node.lsp_binding is not None:
+        bindings.append(
+            LspBinding(
+                node_name=node.id,
+                lsp_server_name=node.lsp_binding.server or "",
+                languages=node.lsp_binding.languages or [],
+                auto_detect=node.lsp_binding.auto if node.lsp_binding.auto is not None else True,
+            )
+        )
+    
+    # Fallback path: check config dict for backward compatibility
     raw_bindings = node.config.get("lsp_bindings", [])
     if not isinstance(raw_bindings, list):
         return bindings
+    
     for entry in raw_bindings:
         if not isinstance(entry, dict):
             continue
@@ -175,6 +200,7 @@ def _extract_lsp_bindings(node: NodeDefinition) -> list[LspBinding]:
                 auto_detect=entry.get("auto_detect", True),
             )
         )
+    
     return bindings