feat(rust): NPC profiles and placements pages, the profile leaderboard (runicnpc stage 4)

Admin: Rust NPC profiles (the form RunicNPC reads, per server, shared or
fleet, each server's push state and refusals, replaced profiles with
Restore) and Rust NPC placements (the live map: click to place, pins for
every placement; edit, rename, respawn, remove). The live map takes a pick
handler and pins, unchanged for the public page.

Public: the leaderboard ranks by a profile's kills (D250), and opening a
row shows that player's kills by profile (D252); the killfeed names a
RunicNPC NPC by its own name. Player: your own kills by profile. Titles: a
rule on a profile's kills picks the profile. npcs.test.js covers the
profile checks, adoption, the push, the picker and verb, the triggers, kill
crediting, titles and placements (481 server tests).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

client/src/lib/mapGeometry.js

@@ -34,6 +34,15 @@ export function toLatLng(g, x, z) {
   return [(Number(z) + half) * s + m, (Number(x) + half) * s + m]
 }
 
+/** The inverse of `toLatLng`: a point on the picture as world `{ x, z }` in metres (a click on the map). */
+export function fromLatLng(g, lat, lng) {
+  const s = scaleOf(g)
+  if (!(s > 0)) return null
+  const half = g.worldSize / 2
+  const m = g.oceanMargin || 0
+  return { x: (Number(lng) - m) / s - half, z: (Number(lat) - m) / s - half }
+}
+
 /** The picture's bounds in the same space. */
 export function boundsOf(g) {
   return [[0, 0], [g.height, g.width]]