Feature/update assessment instructions

[ShawnDigital]

Added a lot of boilerplate grunt work like models, file processing, running tests cases which was not beneficial to the assessment. This should allow them to focus on the primary problem being solved.

[Copilot]

Pull request overview

This PR refactors a coding assessment for a gross-to-net payroll calculator by providing boilerplate code (models, file processing, test harness) so candidates can focus on implementing the core calculation logic in the PayrollCalculator.Calculate method.

Key changes include:

• Removed manual file processing requirements by adding pre-built model classes and test infrastructure
• Replaced basic input files with a comprehensive test harness that automatically validates expected vs actual results
• Updated documentation to clarify requirements and provide clear instructions for running tests

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 15 comments.

Show a summary per file

File	Description
gross-to-net/test-cases.json	Removed old test cases file from root directory
gross-to-net/input.json	Removed old input file from root directory
gross-to-net/dotnet/test-cases.json	Added new comprehensive test cases with 10 scenarios covering various payroll scenarios
gross-to-net/dotnet/models/Withholding.cs	Added model class representing withholding entries (taxes/deductions)
gross-to-net/dotnet/models/Tax.cs	Added model class for tax calculations with support for percentage and capped percentage types
gross-to-net/dotnet/models/PayrollResult.cs	Added model class for calculation results containing gross pay, taxable earnings, withholdings, and net pay
gross-to-net/dotnet/models/Earning.cs	Added model class for earnings supporting both hourly and salary types
gross-to-net/dotnet/models/Deduction.cs	Added model class for deductions with flat and percentage types, pre-tax and post-tax support
gross-to-net/dotnet/Program.cs	Completely rewrote to provide automated test runner with validation, error reporting, and help text
gross-to-net/dotnet/PayrollCalculator.cs	Added stub implementation with TODO for candidates to complete
gross-to-net/dotnet/GrossToNet.csproj	Updated to reference new test-cases.json file instead of old input.json
gross-to-net/directory-structure.txt	Added documentation showing the project structure
gross-to-net/README.md	Rewrote with clearer requirements, calculation formulas, and instructions for building/running tests

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[Copilot]

Spelling error: "Witholding" should be "Withholding".

Suggested change

	- Witholding groups are applied using the following order:
	- Withholding groups are applied using the following order:

[Copilot]

Spelling error: "Commmand-line" has an extra 'm' and should be "Command-line".

Suggested change

	### Commmand-line
	### Command-line

[Copilot]

Unused import: System.Text is imported but not used anywhere in the code.

Suggested change

using System.Text;

[Copilot]

[nitpick] Unnecessary blank line before closing brace. While not incorrect, it's inconsistent with other model classes in the same PR (e.g., Withholding.cs, Tax.cs, PayrollResult.cs, Earning.cs don't have this blank line).

Suggested change

[Copilot]

Misleading error message: The error message references "input.json" but the code is actually loading from a test cases file (either "test-cases.json" or "advanced-test-cases.json" or a custom file). The error message should reference the actual file being loaded.

Suggested change

	throw new Exception("Failed to load payroll data from input.json");
	throw new Exception($"Failed to load payroll data from {testFile}");

[Copilot]

[nitpick] String concatenation readability: The expression "Loading " + testFile + $" from: {filePath}" mixes string concatenation and interpolation. Consider using consistent string interpolation: $"Loading {testFile} from: {filePath}" for better readability.

Suggested change

	Console.WriteLine($"Loading " + testFile + $" from: {filePath}");
	Console.WriteLine($"Loading {testFile} from: {filePath}");

[Copilot]

Spelling error: "Witholdings" should be "Withholdings".

Suggested change

	### Witholdings
	- Types: `tax`, `deductions`
	- Deductions are either Pre-Tax or Post-Tax depending on the `isPrefix` value.
	- Witholding groups are applied using the following order:
	### Withholdings
	- Types: `tax`, `deductions`
	- Deductions are either Pre-Tax or Post-Tax depending on the `isPrefix` value.
	- Withholding groups are applied using the following order:

[Copilot]

Potential null reference exception: testCase.ActualOutput could be null if an exception was thrown during calculation (lines 91-102), but it's being dereferenced here without a null check. This will cause a NullReferenceException when the test runner tries to validate a failed test case.

Suggested change

	var actual = testCase.ActualOutput!;
	if (testCase.Passed == false)
	{
	Console.ForegroundColor = ConsoleColor.Red;
	Console.WriteLine($"\t ✗ Test failed: {testCase.Description} --> {(testCase.Error != null ? $"{testCase.Error.GetType().Name} --> " : string.Empty)}{testCase.Message}");
	Console.ResetColor();
	return;
	}
	if (testCase.ActualOutput == null)
	{
	testCase.Passed = false;
	testCase.Message = "No actual output produced for test case.";
	Console.ForegroundColor = ConsoleColor.Red;
	Console.WriteLine($"\t ✗ Test failed: {testCase.Description} --> No actual output produced.");
	Console.ResetColor();
	return;
	}
	var actual = testCase.ActualOutput!;

[Copilot]

[nitpick] Inconsistent indentation: The closing </ItemGroup> tag has inconsistent indentation compared to line 11. It should align with the opening tag.

Suggested change

	</ItemGroup>
	</ItemGroup>

[Copilot]

Spelling error: "decductions" should be "deductions".

Suggested change

	- Flat decductions have a fixed dollar `value`
	- Flat deductions have a fixed dollar `value`