feat(packages): ludic.vehicles - each player's boat and horse: called to four berths or four bays, made the first time and fetched after, owner and rider, mounting (a hungry horse will not go), riding a horse on stamina and a boat on the wind with steering by signed speed, the swell at the edge, getting off onto the rider's own safe spot, a player leaving; the world and the rider through ports; mounted, dismounted, no landing, moved, swell and hunger as facts; this player's own saved by kind

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.vehicles/ride.ludic

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+# ride.ludic - the rider's stick steers what they are on: a horse walks, canters on stamina and
+# stops at water, a slope or a trunk; a boat rows, drifts on the wind and stops at the shore
+const VE_HORSE_WALK: float = 4.5
+const VE_HORSE_GALLOP: float = 11.0
+const VE_HORSE_ACC: float = 4.0
+const VE_HORSE_TURN: float = 1.6
+const VE_BOAT_TOP: float = 3.2
+const VE_BOAT_ACC: float = 1.2
+const VE_BOAT_TURN: float = 1.1
+
+export function vehicle_update(ix: float, iz: float, run: bool, dt: float) -> void {
+  let v = ve_cur
+  if v == null { return }
+  var top = VE_BOAT_TOP
+  var acc = VE_BOAT_ACC
+  var turn = VE_BOAT_TURN
+  if v.kind == VEHICLE_HORSE {
+    acc = VE_HORSE_ACC
+    turn = VE_HORSE_TURN
+    top = VE_HORSE_WALK
+    if run and v.fuel > 5.0 { top = VE_HORSE_GALLOP }
+  }
+  v.speed = v.speed + Math.clamp(iz * top - v.speed, -acc * dt, acc * dt)
+  if v.kind == VEHICLE_BOAT { ve_swell(v, dt) }
+  # Steering follows SIGNED speed: backing up with the stick left swings the nose right
+  if Math.abs(v.speed) > 0.3 {
+    var rate = Math.clamp(Math.abs(v.speed) / 3.0, 0.4, 1.0)
+    if v.speed < 0.0 { rate = -rate }
+    v.yaw = v.yaw - ix * turn * (dt * rate)
+  }
+  let d = v.speed * dt
+  ve_travel(v, v.x - Math.sin(v.yaw) * d, v.z - Math.cos(v.yaw) * d, d)
+  if v.kind == VEHICLE_HORSE { ve_stamina(v, d, dt) } else { ve_float(v, d, dt) }
+  VehicleWorld.placed(v)
+  VehicleRider.ride_at(v.x, v.y + v.seat_h, v.z, v.yaw, Math.abs(v.speed))
+}
+
+# a boat only where there is water under it; a horse only on dry ground, up a walkable rise, clear
+function ve_travel(v: Vehicle, nx: float, nz: float, d: float) -> void {
+  let nh = VehicleWorld.ground(nx, nz)
+  var ok = true
+  if v.kind == VEHICLE_BOAT { ok = nh < VehicleWorld.water(nx, nz) - 0.35 } else {
+    if nh < VehicleWorld.water(nx, nz) + 0.4 { ok = false }
+    if nh - v.y > Math.abs(d) * 0.9 { ok = false }
+    if VehicleWorld.blocked(nx, nz, 0.8) { ok = false }
+  }
+  if not ok {
+    v.speed = 0.0
+    return
+  }
+  v.x = nx
+  v.z = nz
+  if v.kind != VEHICLE_BOAT { v.y = nh }
+  if Math.abs(d) > 0.0 { ve_say(VEHICLE_MOVED, v, Math.abs(d)) }
+}
+
+# a boat gets a longer leash than a swimmer and the same current at the end of it: the outward
+# part of the stroke only, so a boat at the limit can always be put about
+function ve_swell(v: Vehicle, dt: float) -> void {
+  var fx = -Math.sin(v.yaw)
+  var fz = -Math.cos(v.yaw)
+  if v.speed < 0.0 {
+    fx = -fx
+    fz = -fz
+  }
+  let take = Math.clamp(VehicleWorld.swell(v.x, v.z, fx, fz), 0.0, 1.0)
+  v.speed = v.speed * (1.0 - take)
+  if take > 0.55 and ve_swell_said < 0.0 {
+    ve_swell_said = 14.0
+    ve_say(VEHICLE_SWELL, v, take)
+  }
+  ve_swell_said = ve_swell_said - dt
+}
+
+# a gallop spends stamina and a walk gives it back; every metre costs hay
+function ve_stamina(v: Vehicle, d: float, dt: float) -> void {
+  if Math.abs(v.speed) > 6.0 { v.fuel = Math.max(v.fuel - 6.0 * dt, 0.0) } else { v.fuel = Math.min(v.fuel + 3.0 * dt, 100.0) }
+  v.food = Math.max(v.food - Math.abs(d) * 0.02, 0.0)
+}
+
+# the bob on the water, higher in a wind, and the wind pushing the boat across the lake
+function ve_float(v: Vehicle, d: float, dt: float) -> void {
+  v.bob = v.bob + dt
+  let w = VehicleWorld.wind()
+  v.y = VehicleWorld.water(v.x, v.z) + (0.02 + (0.05 + 0.12 * w) * Math.sin(v.bob * 1.4))
+  let push = w * 0.6 * dt
+  let wx = v.x - Math.sin(VehicleWorld.wind_yaw()) * push
+  let wz = v.z - Math.cos(VehicleWorld.wind_yaw()) * push
+  if VehicleWorld.ground(wx, wz) < VehicleWorld.water(wx, wz) - 0.35 {
+    v.x = wx
+    v.z = wz
+  }
+}
+
+# the boats nobody is in ride the swell where they lie
+export function vehicles_tick(dt: float) -> void {
+  let l = ve_all()
+  for i in 0 .. len(l) {
+    let v = l[i]
+    if v.kind == VEHICLE_BOAT and v.rider < 0 {
+      v.bob = v.bob + dt
+      v.y = VehicleWorld.water(v.x, v.z) + (0.02 + 0.04 * Math.sin(v.bob * 1.1))
+      VehicleWorld.placed(v)
+    }
+  }
+}