Upgrade SharpCompress from 0.38.0 to 0.47.x (breaking API change)

[GoodOlClint]

Context

Dependabot PR #9 bumps SharpCompress from 0.38.0 to 0.47.3, but the build fails because SharpCompress 0.45.0+ replaced its synchronous API with async-only methods.

What breaks

OvfMetadata.cs (ExtractOvfFromTar method, lines 89-99) uses three APIs that no longer exist:

• ReaderFactory.Open(stream) → now returns ValueTask<IReader> (must be awaited)
• reader.MoveToNextEntry() → replaced by MoveToNextEntryAsync()
• reader.OpenEntryStream() → replaced by OpenEntryStreamAsync()

Scope

SharpCompress is used in exactly one file: src/PSProxmoxVE.Core/Models/Vms/OvfMetadata.cs for extracting OVF metadata from OVA archives (used by Import-PveOva).

Fix

Convert ExtractOvfFromTar() and FromOva() to async, then call with .GetAwaiter().GetResult() at the cmdlet level (consistent with the project's sync-over-async pattern per DECISIONS.md F048/D001).

Estimated effort: ~30 minutes, 2-3 methods to change.

References

• Dependabot PR: Bump SharpCompress from 0.38.0 to 0.47.3 #9
• SharpCompress releases
• Current version 0.38.0 has no known vulnerabilities — this is a modernization upgrade, not a security fix.