Wildlife and nature: animals, beehives, bushes, flowers, rocks, logs

New stdlib module wildlife.rhai:
- Animals (new palette category): Deer (stag with antlers, does, fawns),
  Wild boar, Fox, Elephant (bull with tusks, cow, calf), Rabbits. Low-poly
  solids from faces (loft, tube), parts drawn back to front by depth, faces
  edged in their own shade (class beast). Herds scatter round a spot, each
  animal its own sprite facing about the object's rotation. Grazing
  animals switch between two head poses (iso-pose2 groups), elephants curl
  their trunks, rabbits hop.
- Birds and Butterflies as flocks: swim() takes a shape (bird, fly, bee);
  wings flap out of step. Fish output unchanged.
- Beehives on stands with supers, lids, entrances and bees flying round;
  Bush (round, flowering, berries); Flowers (bed in rows or meadow); Rocks;
  Log or stump. g-meadow and g-soil ground materials.
- polyline() takes 3D points as documented (antlers).

Theme colours for dark and light, viewer CSS for poses, flapping, hopping.
examples/country: elephants in a paddock with a cut corner, deer at a
forest edge, boar, fox, rabbits, an apiary by a meadow, a pond, a lane,
fence and hedgerow at angles; Country demo in the web Studio and deploy.
MCP guidance, README, SCRIPTING, ROADMAP.

Tests: Rust 78, Studio 122; existing examples draw the same (only the
embedded theme CSS grew).

crates/isokit-project/src/mcp.rs

@@ -27,6 +27,8 @@ Fences (props.style: mesh, wood, bars, half stone, cobble, brick) and site walls
 meet, so for a plot boundary put each piece's ends exactly on the next piece's end or line. Line pieces (roads, walls, \
 fences, hedges, house walls) can run at any angle: a piece from (x0, y0) to (x1, y1) has x, y = the midpoint, \
 w = the distance and rot = atan2(y1 - y0, x1 - x0) in degrees; where diagonal pieces meet, corners are mitred. \
+Animals (category Animals: deer, boar, fox, elephant, rabbits, birds, butterflies) are herds: props.n animals \
+scattered within props.r metres of x, y, facing about the rotation; keep them out of roads, ponds and buildings. \
 Production lines (category Industry): a producer (props.rate per minute, product) puts goods out on its local +x \
 side; a conveyor (rot 0 runs towards +x, 90 +y, 180 -x, 270 -y; w = length, props.speed m/s) starting exactly \
 at that side carries them, and a conveyor whose start is at another's end carries on with them (corners join). \

crates/isokit-project/tests/demo.rs

@@ -72,7 +72,7 @@ fn demo_passes_the_check() {
     assert!(f.is_empty(), "{f:?}");
 }
 
-/// The house, factory and streets demos: every view draws every object without warnings
+/// The house, factory, streets and country demos: every view draws every object without warnings
 /// or depth-sort cycles (walls and belts must not overlap), and the projects pass the check.
 #[test]
 fn house_demo_renders_every_view_cleanly() {
@@ -89,6 +89,11 @@ fn streets_demo_renders_every_view_cleanly() {
     example_renders_every_view_cleanly("streets");
 }
 
+#[test]
+fn country_demo_renders_every_view_cleanly() {
+    example_renders_every_view_cleanly("country");
+}
+
 fn example_renders_every_view_cleanly(name: &str) {
     let p = Project::load(
         Path::new(env!("CARGO_MANIFEST_DIR"))