GroundZeroCore Resource Pack v25

Built from v24.

Changes:
- Added casino resource icons:
  custom_model_data 9200: casino_slot_machine
  custom_model_data 9201: casino_horse_betting
  custom_model_data 9202: casino_blackjack
  custom_model_data 9203: casino_vault
  custom_model_data 9204: casino_chips
  custom_model_data 9205: casino_ticket
  custom_model_data 9206: casino_stats
- Added missing fallback item textures referenced by item models to prevent purple/black missing icons.
- Replaced moving/warped menu panorama with a static Minecraft-style GroundZero scene.
- Made default Minecraft title/edition transparent because the GroundZero title is in the static menu art.
- Existing GroundZero drug, police, paper and mechanics textures were preserved.

Validation:
{
  "json_errors": 0,
  "missing_model_textures": 0,
  "casino_textures_added": true,
  "casino_models_added": true,
  "casino_core_icon_helpers": true,
  "existing_drug_texture_kept": true,
  "existing_police_texture_kept": true,
  "existing_papers_kept": true,
  "static_menu_faces": true
}

Remaining missing model textures:
[]
