Document SQLite persistence and local reset behavior

FAQ.md

@@ -14,3 +14,12 @@ This keeps the first commit small while preserving CI discipline. Additional too
 ## Is frontend JavaScript handwritten?
 
 No. Frontend source code lives in `RpgRoller/frontend/*.ts` and is compiled to `RpgRoller/wwwroot/*.js` for browser delivery.
+
+## Where is backend state stored locally?
+
+Backend state is persisted via EF Core + SQLite.
+
+- Development default: `RpgRoller/App_Data/rpgroller.development.db`
+- Non-development default: `RpgRoller/App_Data/rpgroller.db`
+
+To start with a clean backend state, stop the app and remove the corresponding SQLite file.

README.md

@@ -7,6 +7,13 @@ Fresh full-stack starter scaffold:
 - `RpgRoller.Tests/`: xUnit integration-heavy test project
 - `RpgRoller.sln`: solution used by local CI script
 
+Backend state persistence:
+
+- EF Core with SQLite (`Microsoft.EntityFrameworkCore.Sqlite`)
+- Development DB: `RpgRoller/App_Data/rpgroller.development.db`
+- Default DB: `RpgRoller/App_Data/rpgroller.db`
+- Database schema is created automatically on startup (`EnsureCreated`)
+
 ## Prerequisites
 
 - .NET SDK 10.0+
@@ -25,6 +32,8 @@ Fresh full-stack starter scaffold:
    ```
 3. Open `http://localhost:5000` (or the port shown in the console).
 
+To use a custom SQLite database path, set `ConnectionStrings__RpgRoller`.
+
 ## Frontend Tooling
 
 - OpenAPI contract: `openapi/RpgRoller.json`

TECH.md

@@ -6,6 +6,7 @@
 - Backend/full-stack project: `RpgRoller` (Minimal API + static `wwwroot` frontend)
 - Frontend source: `RpgRoller/frontend` (TypeScript)
 - Test project: `RpgRoller.Tests` (xUnit + `WebApplicationFactory` integration tests)
+- Persistence: EF Core + SQLite (`RpgRoller/Data/RpgRollerDbContext.cs`)
 - OpenAPI source: `openapi/RpgRoller.json`
 - Generated client source: `RpgRoller/frontend/generated/api-client.ts`
 - Generated client output: `RpgRoller/wwwroot/generated/api-client.js`
@@ -16,11 +17,11 @@
 ## 1) Stack and baseline choices
 
 - ASP.NET Core Minimal API on .NET 10.
-- EF Core + Database in current project (single-node deployment).
+- EF Core with SQLite file persistence in current project (single-node deployment).
 - Cookie authentication (`HttpOnly`, `SameSite=Strict`, secure in production).
 - A minimal frontend framework supporting mixing 3D graphics with 2D elements, or a modern framework-less alternative (HTMl/CSS/TypeScript).
 - OpenAPI generated from backend and consumed by generated client.
-- xUnit integration-heavy test suite with in-memory Database and coverage gates.
+- xUnit integration-heavy test suite with isolated SQLite test databases and coverage gates.
 
 ## 2) Architecture patterns to keep
 
@@ -78,7 +79,7 @@ This pattern is a strong baseline for low to medium scale and should be the defa
 
 ### 2.5 Data and invariants
 
-- Strong DB models
+- Strong DB models backed by SQLite
 - DB-level guardrails (trigger) to complement app-level checks
 - EF patterns:
   - `AsNoTracking()` for read-only queries