fix: epoch graffiti bug

[BlobMaster41]

Description

Fix critical graffiti bug.

[BitcoinTransactionVerificatorV2 ERROR]: Error verifying Bitcoin Transaction V2: OP_NET: Invalid epoch submission feature data length. (84 bytes [f646158e5848a8a650f108883c7c8773084d0c735bdaefb3f9e593f42707a64ba148ecf8275abc319d930f56ae90b0f28ee0e6c6405fdf5800033118bf5dac09000000104f504e45542e4f524700000000000000])

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Performance improvement
• Consensus change (changes that affect state calculation or validation)
• Refactoring (no functional changes)
• Documentation update
• CI/CD changes
• Dependencies update

Checklist

Build & Tests

• npm install completes without errors
• npm run build completes without errors
• npm test passes all tests

Code Quality

• Code follows the project's coding standards
• No new compiler warnings introduced
• Error handling is appropriate
• Logging is appropriate for debugging and monitoring

Documentation

• Code comments added for complex logic
• Public APIs are documented
• README updated (if applicable)

Security

• No sensitive data (keys, credentials) committed
• No new security vulnerabilities introduced
• RPC endpoints properly authenticated
• Input validation in place for external data

OP_NET Node Specific

• Changes are compatible with existing network state
• Consensus logic changes are documented and tested
• State transitions are deterministic
• WASM VM execution is reproducible across nodes
• P2P protocol changes are backward-compatible (or migration planned)
• Database schema changes include migration path
• Epoch finality and PoC/PoW logic unchanged (or documented if changed)

Testing

Consensus Impact

Related Issues

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