feat(#9): Tpac file parser service

[ModerRAS]

Summary

• Create ITpacParserService interface
• Implement TpacParserService to parse .tpac files
• Extract model IDs, names, and types from tpac files
• Add comprehensive unit tests

Changes

• BannerlordModEditor.Common/Services/TpacParserService.cs - Implementation
• BannerlordModEditor.Common.Tests/Services/TpacParserServiceTests.cs - Unit tests

Closes #9

[Copilot]

Pull request overview

Introduces a .tpac file parsing service with an interface and DTOs, plus xUnit tests to validate parsing behavior.

Changes:

• Added ITpacParserService plus TpacParserService implementation to parse .tpac files and extract model metadata.
• Added DTOs (TpacFileInfo, TpacModelInfo) to return parsed results and errors.
• Added xUnit tests covering extension detection and basic parsing flows.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 6 comments.

File	Description
BannerlordModEditor.Common/Services/TpacParserService.cs	Adds .tpac parser service, DTOs, and interface for parsing/extracting models.
BannerlordModEditor.Common.Tests/Services/TpacParserServiceTests.cs	Adds xUnit tests for .tpac extension checks and model extraction.

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[Copilot]

Path.GetTempFileName() creates a file with a .tmp extension, but ParseTpacFile rejects non-.tpac extensions via IsTpacFile. This test will fail by returning IsValid = false with "Not a valid .tpac file". Create the temp path with a .tpac extension (e.g., Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".tpac")) and write to that path instead.

[Copilot]

Same issue as the sync test: the temp file will have a .tmp extension, so ParseTpacFileAsync will return invalid due to IsTpacFile. Use a temp file path ending in .tpac to align the test with the service’s validation logic.

[Copilot]

ExtractModels swallows all exceptions and returns whatever it has collected (often an empty list). Because ParseTpacFile treats “no exception” as success, an IO/parsing failure can incorrectly produce IsValid = true with Models = []. Remove the empty catch and let exceptions propagate to ParseTpacFile (so it can set IsValid = false), or catch and rethrow a more specific exception that preserves the original as an inner exception.

Suggested change

	try
	{
	var content = File.ReadAllText(tpacFilePath);
	var lines = content.Split('\n', StringSplitOptions.RemoveEmptyEntries);
	var currentModel = new TpacModelInfo();
	foreach (var line in lines)
	{
	var trimmed = line.Trim();
	if (trimmed.StartsWith("model_id:", StringComparison.OrdinalIgnoreCase))
	{
	if (!string.IsNullOrEmpty(currentModel.ModelId))
	{
	models.Add(currentModel);
	}
	currentModel = new TpacModelInfo
	{
	ModelId = trimmed["model_id:".Length..].Trim()
	};
	}
	else if (trimmed.StartsWith("model_name:", StringComparison.OrdinalIgnoreCase))
	{
	currentModel.ModelName = trimmed["model_name:".Length..].Trim();
	}
	else if (trimmed.StartsWith("model_type:", StringComparison.OrdinalIgnoreCase))
	{
	currentModel.ModelType = trimmed["model_type:".Length..].Trim();
	}
	else if (trimmed.Contains(':'))
	{
	var parts = trimmed.Split(':', 2);
	if (parts.Length == 2)
	{
	currentModel.Properties[parts[0].Trim()] = parts[1].Trim();
	}
	}
	}
	if (!string.IsNullOrEmpty(currentModel.ModelId))
	{
	models.Add(currentModel);
	}
	}
	catch
	{
	var content = File.ReadAllText(tpacFilePath);
	var lines = content.Split('\n', StringSplitOptions.RemoveEmptyEntries);
	var currentModel = new TpacModelInfo();
	foreach (var line in lines)
	{
	var trimmed = line.Trim();
	if (trimmed.StartsWith("model_id:", StringComparison.OrdinalIgnoreCase))
	{
	if (!string.IsNullOrEmpty(currentModel.ModelId))
	{
	models.Add(currentModel);
	}
	currentModel = new TpacModelInfo
	{
	ModelId = trimmed["model_id:".Length..].Trim()
	};
	}
	else if (trimmed.StartsWith("model_name:", StringComparison.OrdinalIgnoreCase))
	{
	currentModel.ModelName = trimmed["model_name:".Length..].Trim();
	}
	else if (trimmed.StartsWith("model_type:", StringComparison.OrdinalIgnoreCase))
	{
	currentModel.ModelType = trimmed["model_type:".Length..].Trim();
	}
	else if (trimmed.Contains(':'))
	{
	var parts = trimmed.Split(':', 2);
	if (parts.Length == 2)
	{
	currentModel.Properties[parts[0].Trim()] = parts[1].Trim();
	}
	}
	}
	if (!string.IsNullOrEmpty(currentModel.ModelId))
	{
	models.Add(currentModel);

[Copilot]

ParseTpacFileAsync uses Task.Run to offload synchronous IO, which consumes a thread-pool thread and doesn’t provide true async IO. Prefer an actually-async pipeline (e.g., File.ReadAllTextAsync or streaming with StreamReader.ReadLineAsync) and parse from the async-read content; this scales better under concurrency and avoids unnecessary thread-pool usage.

Suggested change

	public async Task<TpacFileInfo> ParseTpacFileAsync(string filePath)
	{
	return await Task.Run(() => ParseTpacFile(filePath));
	public Task<TpacFileInfo> ParseTpacFileAsync(string filePath)
	{
	return Task.FromResult(ParseTpacFile(filePath));

[Copilot]

The behavior for invalid extensions (setting IsValid = false and the specific error message) isn’t covered by tests. Add a unit test that writes valid .tpac-formatted content to a non-.tpac filename (or passes such a path) and asserts IsValid is false and ErrorMessage equals "Not a valid .tpac file".

[Copilot]

Property extraction into TpacModelInfo.Properties is a core part of the parser, but the tests currently don’t assert that properties are captured correctly. Add assertions in ParseTpacFile_ExtractsModelsFromValidFile to verify property1/property2 exist with expected values on the first model.