Add NosArchive read/write for legacy .NOS containers

[erwan-joly]

Summary

• Exposes a public static NosArchive type with Read(byte[]) / Write(IReadOnlyList<Entry>) for the legacy file-list + XOR-obfuscated payload layout used by NScliData_*.NOS, NSlangData_*.NOS, etc.
• Each entry preserves its Id and the unknown 4-byte header field verbatim so round-trips are byte-faithful after decryption.
• Version bumped 4.0.0 → 4.1.0 (new public API).

Consumers can now rewrite strings inside inner files (e.g. the NosMall URL in conststring.dat) and repack without shelling out to external tools like OnexExplorer.

Test plan

• Builds with TreatWarningsAsErrors=true + GenerateDocumentationFile=true
• Round-trip test: Read → Write → Read produces decrypted-content-identical entries on NScliData_FR.NOS
• Tag 4.1.0 to trigger NuGet release via .github/workflows/dotnet.yml

🤖 Generated with Claude Code

Summary by CodeRabbit

• New Features

  • Added support for reading and writing legacy NosTale .NOS archive files with encryption/decryption capabilities for archive contents.

• Chores

  • Version updated to 4.1.0

[coderabbitai]

Caution

Review failed

Pull request was closed or merged during review

Walkthrough

A new NosArchive static utility class is added to handle legacy NosTale .NOS archive format parsing and serialization. It includes an Entry record and Read/Write methods for decrypting and encrypting archive contents. The project version is incremented to 4.1.0.

Changes

Cohort / File(s)	Summary
Archive Format Handler src/NosCore.ParserInputGenerator/Extractor/NosArchive.cs	New utility class providing Read method to parse .NOS archives with decryption (handling 0xFF sentinel expansion, packed-nibble mode, and XOR operations), and Write method to serialize entries back with encryption logic (chunked processing, 0x0D mapping).
Project Configuration src/NosCore.ParserInputGenerator/NosCore.ParserInputGenerator.csproj	Version bump from 4.0.0 to 4.1.0.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: adding read/write functionality for legacy .NOS archive containers, which is the primary focus of the changeset.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feat/nos-archive-read-write

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