feat: add C03 projects metadata and new BCR fields

[blushi]

Description

ref: regen-network/regen-registry#1606

We should add BeZero Carbon Rating (BCR) value and link to project anchored metadata, see examples in https://www.notion.so/regennetwork/8c3d639f3da24ffe8a7cd81db5adcd30?v=c2f8ac9017814e4580f6b6b1e322be17

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