feat(packages): ludic.session - a party's roster (slot 0 a port, the others as reported), the roles and who owns the world, the shared night, votes and a world-changing act asking the party; joins, leaves, roles, votes and the night as facts

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

packages/ludic.session/near.ludic

@@ -0,0 +1,30 @@
+# near.ludic - the world asks who is nearest, never "the player": an animal notices whoever is
+# closest, a camper keeps clear of everyone
+export function ply_near_d2(x: float, z: float) -> float {
+  session__near_i = 0
+  var best = 0.0
+  var first = true
+  for p in 0 .. PLY_MAX {
+    if not ply_on(p) { continue }
+    let dx = x - ply_x(p)
+    let dz = z - ply_z(p)
+    let d2 = dx * dx + dz * dz
+    if first or d2 < best {
+      best = d2
+      session__near_i = p
+      first = false
+    }
+  }
+  return best
+}
+
+# the distance to the nearest player, in metres; ply_near_i() says which
+export function ply_near(x: float, z: float) -> float { return Math.sqrt(ply_near_d2(x, z)) }
+
+export function ply_near_i() -> int { return session__near_i }
+
+export function ply_dist(p: int, x: float, z: float) -> float {
+  let dx = x - ply_x(p)
+  let dz = z - ply_z(p)
+  return Math.sqrt(dx * dx + dz * dz)
+}