Green ECC Synthesis Update Report

• Updated: 04_material_systems/green_ecc.md
• Created: 07_visualization/green_ecc_strategy_map.md
• Backup: 04_material_systems/green_ecc.md
• Link validation completed.

Missing refs

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    "03_papers/sustainable_ecc_extension/fan-2025-sea-coral-sand-in-marine-engineered_paper_card.md"
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  "07_visualization/green_ecc_strategy_map.md": []
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