Phase 3: strong flyers only spawn in high-level zones

- tools/zone_spawns.py: a species ridable through the air with top
  speed >= 60 or top stamina >= 85 never spawns in a zone whose band
  starts below Lv 30; lines that start as one are only placed in such
  zones, and the tool refuses to write pools that break the rule.
  Drampa moves to Sunscorch; Aerodactyl is fossil-only; Salamence never
  spawns wild (Bagon and Shelgon stay in the Dripstone caves).
- Ride stats stay Cobblemon's until play-tested (species_additions can
  override riding later).
- Phase 3 checklist: all steps in, approval checkpoint for Adrian.

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

docs/balance.md

@@ -28,6 +28,9 @@ Every tunable lives in a config file or in this table. **Placeholder** means gue
 | Guardian drops | Button Isle 10 Poké Balls + 4 Potions; Southwold 6 Great Balls + 4 Exp. Candy S; Westmarch and Jungle Mire Waders + 4 Pecha Berries + 2 Exp. Candy M; Mire and Highlands 3 Icy Rocks + 4 Super Potions; Sunscorch 3 Heat Rocks + 2 Exp. Candy L; Frostpeak and Deep Dark 3 Icy Rocks + 2 Exp. Candy L; Deep Sea Mystic Water + 3 Exp. Candy M | Placeholder | `world/zones.json` → `guardian.drops` | 3 rocks make one full fur or hide set |
 | Mire poison | Poison I for 7 s, renewed every 5 s while in the Mire without Mire Waders | Placeholder | `datapacks/core/data/cobblesurvival/zone_hazards/mire.json` | Vanilla Poison stops at half a heart |
 | Level pressure | full experience up to 5 levels above the zone's band, then 10 % less per level, at least 10 % (Exp. Candy and commands exempt) | Placeholder | `world/zones.json` → `level_pressure` | E.g. on Button Isle (up to Lv 10): Lv 15 full, Lv 20 half, Lv 24+ a tenth |
+| Strong flyer | ridable through the air with top speed ≥ 60 or top stamina ≥ 85 (Cobblemon ride stats) | Placeholder | `tools/zone_spawns.py` (`STRONG_FLYER_*`) | 29 species |
+| High zone for strong flyers | band starts at Lv 30 or more (Sunscorch, Frostpeak, Deep Sea, Deep Dark, Basalt Furnace) | Placeholder | `tools/zone_spawns.py` (`HIGH_ZONE_LEVEL`) | |
+| Ride stats (speed, stamina, ...) | Cobblemon's own | To tune after play-testing | species `riding` via `species_additions` | |
 | Healing while sleeping | off (`healPercent` 0) | Decided (roadmap) | `config/cobblemon/main.json` | |
 | Loot container refresh | 1 hour (72,000 ticks of game time) after first opened, all containers | Decided (Adrian, 2026-10-29) | `config/lootr-common.toml` | Tiering by structure/biome later |
 | Gamerules in the template | `doMobSpawning false` | Decided (Adrian, 2026-10-28; may be reverted later) | `world/world.json` → `gamerules` | Pokémon spawning is Cobblemon's own `doPokemonSpawning` |