feat(scenario): run logs, lint/format tooling, CONTRIBUTING

- add ScenarioRunLogEntity to persist step script output to DB
- stepLogger dual-writes to NestJS logger and DB (fire-and-forget)
- add GET /scenarios/:id/run/:runId returning run, stepRuns and logs
- add POST /scenarios/:id/run/:runId/wait (polls until terminal state)
- 9 new integration tests for the two endpoints (136 total)
- add eslint with typescript-eslint and eslint-config-prettier
- add npm scripts: format, lint, lint:fix
- resolve all lint errors across src and test (no any types)
- add CONTRIBUTING.md covering dev workflow

CONTRIBUTING.md

@@ -0,0 +1,133 @@
+# Contributing
+
+## Prerequisites
+
+- Node.js 20+
+- Docker + Docker Compose
+
+Install dependencies:
+
+```bash
+npm install
+```
+
+Copy `.env.example` to `.env` and fill in the required values before running.
+
+---
+
+## Starting the application
+
+**Development** (watch mode, restarts on file changes):
+
+```bash
+npm run start:dev
+```
+
+**Production build, then start**:
+
+```bash
+npm run build
+npm run start:prod
+```
+
+The application listens on port **3000** by default.
+
+---
+
+## Running tests
+
+```bash
+npm run test
+```
+
+Run a single spec file:
+
+```bash
+npm run test -- --no-coverage test/scenario.controller.spec.ts
+```
+
+Watch mode:
+
+```bash
+npm run test:watch
+```
+
+Enable verbose NestJS log output during tests:
+
+```bash
+npm run test:debug
+```
+
+---
+
+## Formatting code
+
+[Prettier](https://prettier.io/) is used to format all TypeScript source and test files:
+
+```bash
+npm run format
+```
+
+This rewrites `src/**/*.ts` and `test/**/*.ts` in place.
+
+---
+
+## Linting
+
+[ESLint](https://eslint.org/) with `typescript-eslint` and `eslint-config-prettier` is used:
+
+```bash
+# report issues
+npm run lint
+
+# report and auto-fix where possible
+npm run lint:fix
+```
+
+The project targets zero errors. Run lint before committing.
+
+---
+
+## Building the container
+
+```bash
+docker compose build
+```
+
+To rebuild without the layer cache:
+
+```bash
+docker compose build --no-cache
+```
+
+---
+
+## Running with Docker Compose
+
+Start (detached):
+
+```bash
+docker compose up -d
+```
+
+Build and start in one step:
+
+```bash
+docker compose up -d --build
+```
+
+The application is exposed at **http://localhost:13000**.
+
+SQLite data is persisted in `./data/` and key files are mounted from `./keys/` — both directories are volume-mounted into the container.
+
+Stop and remove containers:
+
+```bash
+docker compose down
+```
+
+View logs:
+
+```bash
+docker compose logs -f
+```