Cryptid Core Co Field Operations

0.7.0-a — Stage 7a: Biome Bigfoots + Watchtower (part 1 of Stage 7)

- NEW: Desert Bigfoot (deserts + savannas) and Jungle Bigfoot (jungles) —
  sand-tan and moss-green morphs, 85% of in-biome spawns, all age classes.
- NEW: Watchtower — a lone CCC fire-watch tower in forest biomes. Climb it.
- NEW: per-variant Bigfoot footprints — every fur color leaves its own print.
- NEW: per-variant plaster casts — cast blocks and cast items now carry the
  fur color visually. 32 collectible cast combinations.
- NEW: deer hides — every deer drops a hide matching its variant (7 hides).
- FIX: boat houses spawned 2 White Bigfoots instead of 1, and their fur
  rendered brown while the game called them White Bigfoot. Both fixed.
- FIX: Cherry footprint casts displayed as "Brown" due to a color wrap bug.
  Existing casts fix themselves on load.