TerraNexus Additions

First Version of this project

• Added road construction, bridge, and drainage blocks.
• Added the TerraNexus: Road Construction creative tab.
• Integrated models, textures, recipes, loot tables, tags, and translations.
• Organized resources into clear thematic categories.
• Added new models and galvanized textures for standard guardrails.
• Implemented a guardrail oxidation system with the following stages:
• Galvanized
• Lightly Rusted
• Heavily Rusted
• Aligned oxidation behavior with the vanilla copper oxidation system.
• Rusted guardrails can be scraped back using an axe.
• Guardrail oxidation can be disabled via config/tnadditions/guardrails/oxidation.json.
• Corrected guardrail orientation, dimensions, and selection hitboxes.
• Improved guardrail inventory models.
• Added a shared asphalt texture for the block, slab, and stairs.
• Cleaned up the project structure and resource organization.
• Verified client, server, and build compatibility for Minecraft 1.21.8.