Feature/update readme sample

[PhenX]

No description provided.

[Copilot]

Pull request overview

Updates the samples/ReadmeSample project into a runnable “feature tour” that demonstrates the full README feature set using a local SQLite database and richer console output.

Changes:

• Switches the sample to SQLite + Spectre.Console and adds a comprehensive per-feature walkthrough in Program.cs.
• Expands the sample domain model (status enum, supplier navigation, DTO projection) to cover all documented features.
• Adds a detailed samples/ReadmeSample/README.md explaining how to run the sample and what each feature does.

Reviewed changes

Copilot reviewed 14 out of 15 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
samples/ReadmeSample/ReadmeSample.csproj	Moves the sample to net10.0 and swaps package references to SQLite + Spectre.Console.
samples/ReadmeSample/README.md	New end-user documentation for running and understanding the sample.
samples/ReadmeSample/Program.cs	Rewrites the entry point into 11 feature demos with SQL + result printing.
samples/ReadmeSample/Extensions/UserExtensions.cs	Adds README-aligned [Projectable] extension methods, including overloads.
samples/ReadmeSample/Entities/User.cs	Modernizes the entity (file-scoped namespace, required props, init collection).
samples/ReadmeSample/Entities/Supplier.cs	Adds optional supplier entity for null-conditional demo.
samples/ReadmeSample/Entities/Product.cs	Adds optional supplier navigation + [Projectable] SupplierName.
samples/ReadmeSample/Entities/OrderStatus.cs	Adds enum + extension method for enum expansion demo.
samples/ReadmeSample/Entities/OrderItem.cs	Cleans up entity + nullability initialization.
samples/ReadmeSample/Entities/Order.cs	Adds multiple [Projectable] members covering several features.
samples/ReadmeSample/Dtos/OrderSummaryDto.cs	Adds DTO with [Projectable] constructor for projection demo.
samples/ReadmeSample/ConsoleHelper.cs	Adds Spectre.Console rendering helpers (SQL highlighting, formatting).
samples/ReadmeSample/ApplicationDbContext.cs	Switches to SQLite and configures UseProjectables().
Directory.Packages.props	Adds central package version for Spectre.Console.
.gitignore	Ignores the generated ReadmeSample.db file.