Fix all Copilot review suggestions from Batches 4/7/10

[JusterZhu]

Fixes for Copilot review comments

PR #368 (Batch 4) — 6 items

1. ClientUpdateStrategy: null VersionRespDTO in UpdateInfoEventArgs
2. ClientUpdateStrategy: empty List in MapToProcessInfo causing ProcessInfo constructor throw
3. ClientUpdateStrategy: ignored injected _orchestrator
4. HttpDownloadSource: lost metadata (RecordId, AppType, ReleaseDate)
5. DefaultDownloadOrchestrator: destDir not ensured, SemaphoreSlim not disposed
6. DownloadPlanBuilder: null version handling

PR #374 (Batch 7) — 1 item

7. AbstractBootstrap: DownloadOrchestrator() new() constraint incompatible with DefaultDownloadOrchestrator

PR #380 (Batch 10) — 3 items

8. OSSUpdateStrategy: filename mismatch between download and decompress
9. OSSUpdateStrategy: Url=string.Empty silent failure
10. OSSUpdateStrategy: timeout regression 60s->30s