feat: API 4, factions, escort, allies, tether, turrets, kit extras and PVE (stage 5)

Stage 5's behaviour (docs runicnpc/PLAN.md, D253-D272):

- profiles gain faction, relations (exceptions), alertRadius, turrets,
  hurtByPlayers, hurtsPlayers and kitUse, and the guard role; the faction
  table rides in profiles.json, one row per pair, both ways (D254, D268);
- our own sensing and fight beside Rust's design: only the factions a
  profile hunts, within its leash of its anchor (D263), the target made
  Horror for the length of our own shot, and Rust's attack routine;
- shooting back at whoever hurt it (D268), the alert radius (D256), clan,
  team or player allies that are never targeted and are defended with
  what they own (D257), escort as an order that walks home when its
  charge is gone (D269), and a placement's tether through ZoneManager
  (D272);
- turrets: ignore through CanBeTargeted, and always through a Harmony
  patch on the safe-zone sentries for our always NPCs only (D267);
- the kit's extras, each opted into and used up: heal, melee,
  flamethrower, grenades and rockets (D260, D265);
- TruePVE/NextGenPVE answered both ways unless a profile turns a direction
  off, and the opt-out enforced by RunicNPC itself (D261, D271);
- API 4: RunicNpc_Factions, _SetFactions, _Escort, _Ally, _Tether and the
  OnRunicNpcEscortEnded hook; rnpc follow, rnpc.faction and tether=.

Compiled and loaded on both rigs (Oxide and Carbon); the sentry patch
applies on both.

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

scripts/checkPlugin.test.js

@@ -100,13 +100,13 @@ test('returning null is not good enough — the signature is the rule', () => {
   // `return null` today is one edit away from `return true` tomorrow, and the
   // edit that breaks it looks harmless in a diff. A void method cannot be turned
   // into a veto without changing its signature, which is visible.
-  const methods = `        private bool CanBeTargeted(BaseCombatEntity entity, AutoTurret turret)
+  const methods = `        private bool CanLootEntity(BasePlayer player, StorageContainer container)
         {
             return true;
         }`
 
-  const problems = check(source({ expected: ['CanBeTargeted'], methods }), toml())
-  assert.match(problems[0], /CanBeTargeted returns bool, not void/)
+  const problems = check(source({ expected: ['CanLootEntity'], methods }), toml())
+  assert.match(problems[0], /CanLootEntity returns bool, not void/)
 })
 
 test('a method that is not shaped like a hook is left alone', () => {