feat(rust): NPC sides, the faction table, an event's escort, ally and tether (runicnpc stage 5)

RunicNPC stage 5 on the site (docs runicnpc/PLAN.md, D253-D272):

- profiles gain the guard role, faction, relations (its own exceptions),
  alertRadius, turrets, hurtByPlayers, hurtsPlayers and kitUse, checked in
  RunicNPC's order and words, and defaulting to "players only" (D255);
- the faction table: one site-wide table, one row per pair and both ways
  (D254, D268), stored in rust_npc_factions, edited on the NPC profiles page
  (PUT /admin/rust/npcs/factions), pushed to every server with its
  profiles and hashed with them, and a standalone server's own pairs
  adopted at its first push with the site's winning (D244, D251);
- the Place NPCs step takes escort (a Steam id or a {placeholder}), an ally
  (a clan from the new rust.options.clans source, or the team of a player)
  and tether (the zone this event made), for a RunicNPC profile only
  (D269, D270, D272);
- a placement may be held inside a zone (tether, D272);
- the bridge's RunicNPC API floor is 4.

Tests: 488 server, 66 client. routes.manifest.json regenerated against the
pinned core (one route added).

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

server/router/admin/npcs.controller.js

@@ -137,8 +137,20 @@ async function respawnPlacement(req, res) {
   }
 }
 
+/** Stage 5 (D254, D268): replaces the site's faction table, pushed to every server with the profiles. */
+async function setFactions(req, res) {
+  try {
+    const factions = await npcs.setFactions((req.body || {}).factions)
+    await core.activity.log({ req, action: 'rust.npcs.factions.set', detail: { pairs: factions.length } })
+    res.json({ factions })
+  } catch (err) {
+    fail(res, err, 'save the faction table')
+  }
+}
+
 module.exports = {
   describe,
+  setFactions,
   create,
   update,
   remove,