Function summarize_node 

pub fn summarize_node(node: &A11yNode) -> ElementSummary

Project an A11yNode to an ElementSummary (跟 TS summarizeNode in src/core/screen.ts:5-17 1:1).

name priority scan: label → title → text → value → placeholderValue (跟 TS line 11 v1.5 c5i-a S2 同源). text only set when distinct from name.