[feature] Adjust temporary upload settings

[Ghass-M]

Summary

Reduce initial upload parallelism and slice size to improve stability on first-run uploads and lower resource usage on constrained networks/devices.

Changes

• File: src/ByteSync.Client/Services/Communications/Transfers/Uploading/FileUploadProcessor.cs
  • Decrease upload workers from 6 to 2.
• File: src/ByteSync.Client/Services/Encryptions/SlicerEncrypter.cs
  • Set MaxSliceLength to 1 MB (was effectively 4 MB).
  • Remove unused System.Threading.Tasks using.
  • Clean up duplicate/overwritten MaxSliceLength assignment.

Rationale

• Reduce simultaneous slice uploads to avoid saturating bandwidth and hitting server throttles during initial sessions.
• Smaller slice size:
  • Lowers peak memory usage and retry costs.
  • Improves resume granularity and fairness across members.
  • Better behavior on variable/slow connections.

Impact

• Expected: smoother first-time upload experience with lower CPU/memory/network spikes.
• Trade-off: potential reduction in peak throughput; increased number of requests for large files.
• No breaking API changes.

[Copilot]

Pull Request Overview

This PR reduces upload parallelism and slice size to improve stability and resource usage during file uploads. The changes focus on making the initial upload experience more stable on constrained networks and devices.

• Reduced upload worker count from 6 to 2 to prevent bandwidth saturation
• Decreased maximum slice size from 4MB to 1MB for better memory usage and resume granularity
• Code cleanup including fixing variable naming, removing unused imports, and improving error handling

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
FileUploadProcessor.cs	Reduced concurrent upload workers from 6 to 2 and improved exception type specificity
SlicerEncrypter.cs	Set slice size to 1MB, fixed variable naming, removed unused import, and improved async handling
FileUploadProcessorTests.cs	Updated test to verify 2 workers instead of 6 and added null-forgiving operators

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[Copilot]

The CancellationTokenSource is created but never used for actual cancellation. Either remove the using block and pass CancellationToken.None, or connect it to a proper cancellation mechanism. Also, there's a double semicolon at the end of line 108.

Suggested change

	using (var cts = new CancellationTokenSource())
	{
	await cryptoStream.WriteAsync(bytes.AsMemory(0, readBytes), cts.Token);;
	}
	await cryptoStream.WriteAsync(bytes.AsMemory(0, readBytes), CancellationToken.None);

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[paul-fresquet]

👍