Create README.md

Create a README.md file that explains what the database project is for

Author: carlsixsmith-moj

src/Database/README.md

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+# CATS Database Repository
+
+This repository contains the database definition, deployment tooling, and supporting utilities for the **CATS database** using a modern **.NET SQL Project (DbProj, .NET 10)** approach.
+
+---
+
+## 📦 Repository Structure
+
+```
+/ (root)
+│
+├── /src/Database/CatsDb      # SQL Project (database schema)
+├── /src/DatabaseSeeding      # Data seeding & migration project
+```
+
+---
+
+## 🧱 SQL Project (CatsDb)
+
+### What is a SQL Project?
+
+The SQL Project is a **schema-first database project** built using the .NET SQL SDK. It represents the full structure of the CATS database as source-controlled code.
+
+This includes:
+
+- Tables
+- Views
+- Stored Procedures
+- Functions
+- Schemas
+- Constraints & indexes
+- Security objects
+
+### Key Concepts
+
+- Declarative model – define the desired state, not the steps
+- Source-controlled schema
+- Repeatable builds
+- Drift detection
+
+---
+
+## 🚀 Deployment Process (sqlpackage)
+
+The SQL project builds into a `.dacpac` file:
+
+```
+CatsDb.dacpac
+```
+
+### Build
+
+```
+dotnet build
+```
+
+---
+
+### Deploy
+
+```
+sqlpackage /Action:Publish   /SourceFile:CatsDb.dacpac /TargetConnectionString:"<connection-string>" /p:BlockOnPossibleDataLoss=false
+```
+
+### How it Works
+
+- Compares `.dacpac` with target database
+- Generates deployment plan
+- Applies only schema differences
+
+---
+
+### Notes
+
+- Avoid manual DB changes (they can be overwritten)
+- Use PRs for all schema updates
+
+---
+
+## 🌱 Database Seeding Project
+
+### Location
+
+```
+/src/DatabaseSeeding
+```
+
+### Purpose
+
+This project handles **data**, not schema:
+
+- Test data setup
+- Data migrations
+- Backfilling and transformation
+
+### Why Separate?
+
+The SQL Project is schema-only. This project handles:
+
+- Data insertion
+- Data transformation
+
+Keeping them separate ensures clean deployments and clear responsibility.
+
+---
+
+### Execution
+
+```
+dotnet run --project DatabaseSeeding
+```
+
+---
+
+### Best Practices
+
+- Make scripts idempotent
+- Keep migrations small
+- Log changes clearly
+
+---
+
+## 🔄 Workflow
+
+1. Update schema in SQL project
+2. Build to `CatsDb.dacpac`
+3. Deploy via `sqlpackage`
+4. Run DatabaseSeeding
+
+---
+
+## ✅ Summary
+
+- SQL Project → Schema definition
+- sqlpackage → Deployment
+- DatabaseSeeding → Data setup & migration
+
+---
+
+## 🛠️ Requirements
+
+- .NET 10 SDK
+- sqlpackage CLI
+- SQL Server access
+