Goecia: Forgotten Rites

### Added
- Added a new death recovery system with persistent graves and a **Player Doppelganger** encounter.
- Added the new decorative **Crux** block, including medium and large variants.
- Added the new **Celtic Cruz** family: small, medium and large variants.
- Added the new decorative **Flower Glass** block.
- Added new plants and flowers:
  - Green Mushroom
  - Yellowcryph
  - Ashwort
  - Umbral Bloom
- Added new creative tabs for **Crosses** and **Flowers**.
- Added new advancements:
  - No era una leyenda
  - El Infierno te Recuerda
  - Acero Maldito
  - Point of No Return
  - Combustible Impuro
  - Metal del Abismo

### Changed
- Graves now store player inventory, armor, offhand items and experience.
- Cores of Life and corruption are no longer part of the grave recovery flow.
- The Celtic Cruz block can now act as the protected grave block for the death system.
- Reworked recipes and progression for Crux and Celtic Cruz variants.
- Yellowcryph now generates naturally in Birch Forests.
- Rebalanced mod tools, armor values, repair ingredients and mining progression.
- Updated advancement visuals with custom Goecia UI elements.
- Optimized several server-side systems related to rituals, graves and hostile entities.