feat(web): render canonical living hedge maze walls

ARCHITECTURE.md

@@ -342,6 +342,11 @@ bits, and projects changed passages only in cells already visible to that role.
 The browser may correlate a matching server-approved impact stage with an
 already visible bush wall; it never derives or opens topology locally.
 
+Browser hedge rendering derives a bounded canonical edge list solely from the
+current role projection. Its deterministic local SVG selection is presentation
+only: it cannot create maze edges, alter hit testing, retain hidden cells, or
+change authoritative movement and visibility.
+
 Player projections are translated only within their received cells so the
 authoritative `self` cell aligns with the responsive local focal point. That
 point is centered horizontally and 30% down the usable portrait map region;