SW-119 — Add cross-platform critical-path regression suite

[dDevAhmed]

Summary

Run the stabilized critical path across the supported OS/runtime matrix.

Acceptance Criteria

• Windows npm wrapper, test orchestration, deploy security and E2E path are represented;
• Linux/macOS/Windows support contract is preserved;
• no secrets/live Testnet dependency;
• repository checks pass.

Dependencies

• SW-064
• SW-075
• SW-093
• SW-118

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🏷 Labels

• Stellar Wave
• type: test
• area: ci
• priority: P0
• difficulty: high
• points: 200
• workstream: ci