Milestone 148 pr2 v2 debug viewport

[Coasterpete]

Summary

• Add a backend-only debug-viewport-snapshot-v1-from-track-layout-package-v2 command.
• Import TrackLayoutPackageV2 JSON, validate/map/compile/evaluate it, and export validated DebugViewportSnapshotV1.
• Add CLI/help wiring, README docs, diagnostic line support, and focused tests.

Notes

• Authored banking uses existing BankingProfile sampling.
• Heartline offsets are represented as diagnostic connector lines because Snapshot V1 has no dedicated heartline layer.
• Train pose is omitted for tracks shorter than default bogie spacing.

Verification

• dotnet test Quantum.Tests\Quantum.Tests.csproj --nologo
• dotnet test QuantumCoasterWorks.sln --nologo
• Passed: 1706/1706