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