Phase 3: Alpha guardians, one per zone, back 5 hours after a defeat

- Companion mod (zone/Guardians.kt): each zone's guardian stands at the
  zone's sample point, appears when a player is within 96 blocks, stays
  within 24 blocks, is uncatchable and half again as big. Beating it in a
  battle gives every player in the battle its drops; it returns after 5
  hours of game time (Adrian: fixed spots, 5 hours). State lives in the
  world save; /cobblesurvival guardians lists it.
- tools/zone_spawns.py writes data/cobblesurvival/guardians/<zone>.json:
  the strongest walking (or swimming) Pokemon of the zone at band top + 5,
  with the drops from world/zones.json. Boss drops follow Adrian's rule:
  Icy Rocks before Sunscorch, Heat Rocks before Frostpeak.
- Goat Fur and Hoglin Hide recipes make 8 per rock, so one guardian's 3
  rocks pay for one full insulating set.
- Self-test guardian_appears_and_returns; hazard tests cleaned up; the
  zone generator reads Cobblemon's own entries from the field guide's
  hidden_spawns.

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

pack/index.toml

@@ -50,7 +50,7 @@ hash = "6b1b127b16a87b846a5abdbdb442edb8cbd9386562081309a3808eed1325ed1e"
 
 [[files]]
 file = "kubejs/server_scripts/insulation.js"
-hash = "731756b6277ebc41cd258c8f7d1c519593c43914e8b4426ce230d77d5b6d9fe7"
+hash = "026dc5ab98cb13c906d5b6974ea7624014e804c58141f01ec57e077e1e8bb339"
 
 [[files]]
 file = "kubejs/server_scripts/revival_charm.js"