Strict typing, linting, licensing and a README for newcomers

.github/workflows/ci.yml

@@ -32,6 +32,12 @@ jobs:
       - name: Typecheck
         run: npm run typecheck
 
+      - name: Lint
+        run: npm run lint
+
+      - name: Format
+        run: npm run format:check
+
       - name: Test
         run: npm run test
 

.prettierignore

@@ -0,0 +1,4 @@
+dist
+node_modules
+public/assets
+package-lock.json

.prettierrc.json

@@ -0,0 +1,7 @@
+{
+  "singleQuote": true,
+  "semi": true,
+  "printWidth": 100,
+  "trailingComma": "none",
+  "arrowParens": "always"
+}

ASSETS-LICENSE.md

@@ -0,0 +1,45 @@
+# Asset license
+
+Copyright (c) 2026 MateCode. All rights reserved.
+
+The **source code** of Event Chaos is MIT licensed — see [`LICENSE`](LICENSE).
+This document covers the **assets**, which are not.
+
+## What this covers
+
+Everything under [`public/assets/`](public/assets) and [`public/`](public), including:
+
+- Crew portraits, scenario artwork and menu backgrounds
+- Stage element illustrations and FX textures
+- Icons, the social sharing image and the favicon set
+- The art direction described in [`docs/ART_BIBLE.md`](docs/ART_BIBLE.md)
+
+Sounds are synthesised at runtime by `hooks/useSoundSynth.ts`. That file is code
+and falls under the MIT license; the musical and sound design decisions expressed
+by it are covered here.
+
+## Terms
+
+These assets are licensed under
+[Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International](https://creativecommons.org/licenses/by-nc-nd/4.0/)
+(CC BY-NC-ND 4.0).
+
+| You may                                                  | You may not                                  |
+| -------------------------------------------------------- | -------------------------------------------- |
+| Share the assets as they appear here                     | Use them commercially                        |
+| Study them and reference them in write-ups               | Publish modified or derived versions         |
+| Run and fork the project for personal or educational use | Redistribute them as part of another product |
+
+Attribution is required in every case: credit **MateCode** and link back to this
+repository.
+
+## In practice
+
+Fork the repository, read the code, learn from it, change it, run it — all fine,
+and the MIT license on the code is a genuine invitation to do so.
+
+What is not fine is lifting the artwork into another game, an asset pack, a
+template for sale, or a training set for a model.
+
+If you want to use these assets outside those terms, ask:
+[matecode.dev](https://matecode.dev). The answer is not automatically no.