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/db/purge.sql

@@ -20,6 +20,7 @@
 -- registrant owned what.
 
 -- RunicNPC (runicnpc PLAN.md stage 4). Children before `rust_npc_profiles`.
+DROP TABLE IF EXISTS rust_npc_factions;
 DROP TABLE IF EXISTS rust_npc_kills;
 DROP TABLE IF EXISTS rust_npc_sync;
 DROP TABLE IF EXISTS rust_npc_profile_servers;