Solmannen

First release.

Adds Solmannen, a towering sun-headed horror mob for Fabric 1.20.1.

• Fully GeckoLib-animated: idle, walk, curious stare, feast, day worship, night mourning, spasms, and a rise-from-the-ground summon.
• Curious by default. Studies players up close, turns hostile only when struck.
• Faces the real sun position during daytime prayers. Chest glows during the night vigil.
• Madness gaze that punishes staring at his face, warded by a golden helmet or carved pumpkin.
• Vanilla-block summoning ritual: composter plus lightning rod, fed by sacrifices.
• Custom sounds, spawn egg, and three advancements.