feat(web): render canonical living hedge maze walls

docs/PLAYER_UI.md

@@ -63,6 +63,11 @@ blocked-move text. Opened-passage bits in an ordinary cell projection render as
 a permanent trampled bush gap. Effects have one restartable timer and clear on
 pause, result, reset, disconnect, and control reset. Reduced motion is static.
 
+The map draws only a bounded canonical hedge-edge layer generated from current
+received cells. It hashes each visible edge deterministically to choose the
+approved local SVG variant, so the browser neither retains unseen geometry nor
+decides topology. The layer is decorative and cannot receive input.
+
 All remaining Russian system messages use one `role=status` live message rail
 above the application top bar. One connection-loss message has highest priority
 and remains until a successful recovery; other messages deduplicate, replace

docs/UI_STYLE.md

@@ -158,6 +158,35 @@ are not MVP requirements.
   at 34, 40, and 46 CSS pixels. They contain no coordinates, objects,
   ownership, hidden topology, animation, or runtime dependencies.
 
+### Runtime hedge rendering
+
+- The local `/hedges.svg` sprite is derived from the approved review source.
+  It contains only reusable runtime symbols and no scripts, raster data, or
+  external dependencies. The review sheet in `docs/` is never requested by a
+  browser page.
+- A map uses one non-interactive hedge-edge element for each canonical closed
+  or server-opened edge in its current projection. Closed shared edges are
+  owned by their north or west cell; east and south edges are rendered only at
+  the current projection boundary. This bounds a full 32 by 32 map to 2,112
+  hedge elements and avoids duplicated foliage.
+- A stable integer hash of the canonical edge index and orientation selects one
+  of the six approved intact variants. Opened edges select one of the three
+  approved breach variants. The same projection edge always receives the same
+  art without random state, retained exploration, or a protocol field.
+- Gameplay readability takes priority over foliage density. Hedge foliage is
+  at most 20% of one cell, and the center line of every horizontal or vertical
+  symbol must coincide with its authoritative cell edge. Rotation must preserve
+  that center line instead of shifting a vertical hedge through cell centers.
+  Every runtime SVG instance uses the approved `160 x 40` view box scaled to
+  exactly one cell edge; source-coordinate artwork must never overflow into
+  unrelated cells. Cell interiors remain visually quiet and continuous so
+  passages read as open floor rather than as a grid of highlighted rectangles.
+- Hedge edges are decorative, have `pointer-events: none`, sit below map
+  objects and players, and may overhang an edge by at most 15% of a cell. A
+  projection replacement removes all obsolete edge nodes. One restartable
+  breakthrough timer may briefly show the approved breakthrough frame; reduced
+  motion settles immediately on the permanent breach.
+
 ## 8. Responsive behavior
 
 - The minimum supported player viewport is `412 x 916` CSS pixels.