Format also .svelte files with prettier

.github/workflows/format.yml

@@ -14,8 +14,8 @@ jobs:
           node-version: "18"
       - name: Check formatting
         run: |
-          npm i -g prettier
-          prettier . --check
+          npm ci
+          npm run format:check
   pycodestyle:
     runs-on: ubuntu-latest
     steps:

.gitignore

@@ -1,7 +1,8 @@
+node_modules/
+out
 __pycache__
 *.pyc
 server.db
-out
 
 .terraform*
 terraform.tfstate*

.prettierrc.json

@@ -0,0 +1,11 @@
+{
+  "plugins": ["prettier-plugin-svelte"],
+  "overrides": [
+    {
+      "files": "*.svelte",
+      "options": {
+        "parser": "svelte"
+      }
+    }
+  ]
+}

CONTRIBUTING.md

@@ -40,18 +40,18 @@ tofu fmt -check -recursive
 
 This repository uses [Prettier](https://prettier.io/) to format code with its default settings.
 
-To install Prettier, ensure you have Nodejs and npm installed and run `sudo npm i -g prettier`. This install prettier globally to your system.
+To install Prettier, ensure you have Nodejs and npm installed and run `npm ci`. This installs prettier to `node_modules` in this directory.
 
 Format code by running:
 
 ```sh
-prettier . --write
+npm run format
 ```
 
 Check formatting by running:
 
 ```sh
-prettier . --check
+npm run format:check
 ```
 
 ## Run acceptance tests

front-end/src/lib/BarChart.svelte

@@ -13,8 +13,12 @@
   {#each choices as choice}
     <div class="row" title={choice.title}>
       <span>{choice.label}</span>
-      <div class="bar" style="width: {summary.values[String(choice.value)] / summary.count_non_null * 100}%"
-        ></div>
+      <div
+        class="bar"
+        style="width: {(summary.values[String(choice.value)] /
+          summary.count_non_null) *
+          100}%"
+      ></div>
       <span>{summary.values[String(choice.value)]}</span>
     </div>
   {/each}

package.json

@@ -0,0 +1,10 @@
+{
+  "scripts": {
+    "format": "prettier --write .",
+    "format:check": "prettier --check ."
+  },
+  "devDependencies": {
+    "prettier": "^3.5.3",
+    "prettier-plugin-svelte": "^3.3.3"
+  }
+}