feat: support weex exchange

[drgnchan]

Pull Request - Backend

💡 Tip: Recommended PR title format type(scope): description
Example: feat(trader): add new strategy | fix(api): resolve auth issue

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📝 Description

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🎯 Type of Change

• 🐛 Bug fix
• ✨ New feature
• 💥 Breaking change
• ♻️ Refactoring
• ⚡ Performance improvement
• 🔒 Security fix
• 🔧 Build/config change

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🔗 Related Issues

• Closes #
• Related to #

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📋 Changes Made

• add weex exchange support

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🧪 Testing

Test Environment

• OS: macOS 26.2 (25C56)
• Go Version: go version go1.25.3 darwin/arm64
• Exchange: [if applicable] Weex

Manual Testing

• Tested locally
• Tested on testnet (for exchange integration)
• Unit tests pass
• Verified no existing functionality broke

Test Results

Test output here

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🔒 Security Considerations

• No API keys or secrets hardcoded
• User inputs properly validated
• No SQL injection vulnerabilities
• Authentication/authorization properly handled
• Sensitive data is encrypted
• N/A (not security-related)

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⚡ Performance Impact

• No significant performance impact
• Performance improved
• Performance may be impacted (explain below)

If impacted, explain:

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✅ Checklist

Code Quality

• Code follows project style
• Self-review completed
• Comments added for complex logic
• Code compiles successfully (go build)
• Ran go fmt

Documentation

• Updated relevant documentation
• Added inline comments where necessary
• Updated API documentation (if applicable)

Git

• Commits follow conventional format
• Rebased on latest dev branch
• No merge conflicts

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📚 Additional Notes

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By submitting this PR, I confirm:

• I have read the Contributing Guidelines
• I agree to the Code of Conduct
• My contribution is licensed under AGPL-3.0

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🌟 Thank you for your contribution!

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