Restore clean-clone WordToMD dependency

[kiki830621]

Refs #164

Summary

• replace the ignored local packages/word-to-md-swift override with the published GitHub package
• require WordToMD v1.0.0 and record its exact tag revision in Package.resolved
• restore a reproducible clean-clone root package graph

Verification

• RED: clean-clone swift test failed before planning because the ignored local package directory was absent
• GREEN: swift package resolve passed
• full root suite: 31 XCTest + 26 Swift Testing, 0 failures, 4 environment skips
• independent requirements, logic, security, regression, and adversarial reviews: PASS
• git diff --check: PASS

Checklist

• Diagnose
• Implement (02193ce)
• Verify-gated PASS
• No automatic GitHub closing trailer

After merge, use the explicit IDD closing workflow for issue 164 so its checklist gate and closing summary remain auditable.