fix(sdk): encode large chain IDs in zk metadata

[burak33bb]

Summary

• Encode ZK proof metadata chain IDs with BigInt instead of JS bitwise shifts
• Add regression coverage for a chain ID above 32 bits
• Add a patch changeset

Problem

constructZkPoKMetadata writes chainId as a 32-byte uint, but the previous loop used >>>. JavaScript bitwise operators coerce through uint32, so chain IDs above 32 bits were truncated in the proof metadata while zkVerify still sent the full chain_id in the request payload.

Testing

• pnpm --filter @cofhe/sdk exec vitest run --project node core/test/zkPackProveVerify.test.ts
• pnpm --filter @cofhe/sdk lint (passes with existing warnings)
• pnpm --filter @cofhe/sdk build

Not run to completion locally:

• pnpm run test:setup requires TEST_PRIVATE_KEY for @cofhe/test-setup
• pnpm --filter @cofhe/sdk test needs the Playwright browser binary for the web project and the test setup fixture
• pnpm --filter @cofhe/sdk check:types currently fails because @cofhe/test-setup is not generated without setup

[claude]

Claude Code Review

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[changeset-bot]

🦋 Changeset detected

Latest commit: 323b575

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 9 packages

Name	Type
@cofhe/sdk	Patch
@cofhe/abi	Patch
@cofhe/hardhat-3-plugin	Patch
@cofhe/hardhat-plugin	Patch
@cofhe/mock-contracts	Patch
@cofhe/react	Patch
@cofhe/site	Patch
@cofhe/example-react	Patch
@cofhe/foundry-plugin	Patch

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[burak33bb]

Rebased onto the latest master and re-ran the focused SDK test, lint, and build. The change is still focused and ready from my side.

@architect-dev — when you get a chance, could you let me know whether this is still something you'd like to merge? Happy to keep it updated, or close it if it's no longer needed. Thanks!