Ninjacat Skies Core 0.5.21

Lighter everywhere, measured on a real world. A performance pass profiled on a copy of a long-running server. Existing saves load as they are; no ids change. Clients and servers must update together.

• Loom's End costs far less to run. The hub no longer runs natural mob spawning, which could never place anything there (its ground is the void) but still cost about a fifth of the hub's tick. Residents, keepers, breeding and summoning work exactly as before.
• A faster first build of the town. When a new town revision raises the hub, each block type is read once instead of once per box, and cells that already hold the right block are skipped.
• Idle machines rest. Empty Loomframes and Tension Barrels stop checking redstone every tick, a working Loomframe remembers its last sieve answer, and Thread Locks stop scanning their whole neighbourhood once one plate is up.
• Lighter every second. The Clowder lives check, relic tracking and the wreck and arena block queues do less work and allocate less each tick.
• The Fray draws in about half the time, with the same look, and the Tension Post, Remnant and Craftweave table overlay do much less work per frame: the overlay no longer copies the grid and recounts your inventory several times a frame.
• Fixed: Craftweave remembered recipe picks forever; they are now cleared when a server stops, so a single-player world's picks no longer carry into the next world.