Add Blazor frontend for supermarket receipt application

[Copilot]

Implements a Blazor web UI for the supermarket receipt kata with parrot-themed branding.

Changes

New Blazor Project

• SupermarketReceipt.BlazorApp/ - Blazor Server app targeting .NET 10
• References existing SupermarketReceipt library for business logic
• Added to solution file

Core Components

• Services/SupermarketService.cs - Manages catalog, cart state, and checkout flow
  • Single source of truth for product definitions (name, unit, price)
  • Wraps FakeCatalog, Teller, and ShoppingCart from core library
• Pages/Home.razor - Main UI with three sections:
  • Product catalog with configurable quantities
  • Special offers configuration (3-for-2, percentage discount, bulk pricing)
  • Shopping cart and receipt display

UI Features

• Add products to cart with custom quantities
• Configure offers per product (ThreeForTwo, TenPercentDiscount, TwoForAmount, FiveForAmount)
• Generate receipts showing items, applied discounts, and totals
• Parrot emoji branding throughout (🦜)

Running

cd csharp-ms/SupermarketReceipt.BlazorApp
dotnet run
# Navigate to http://localhost:5023

Screenshots

Initial state:

Receipt with 3-for-2 discount applied:

Notes

• Bootstrap libraries excluded via .gitignore (restored at build time)
• Existing test project targets .NET 5 (unavailable) - pre-existing issue, does not affect new code

Original prompt

---

This section details on the original issue you should resolve

<issue_title>I want to have a frontend to test the application</issue_title>
<issue_description>Build a front-end using blazor for me supermarket recept app.</issue_description>

<agent_instructions>Use extra parrots</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes I want to have a frontend to test the application #27

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