Enforce TypeScript formatting with Biome (#1456)

This builds on the existing Biome setup for the TypeScript code.

I found that 'just ts::fmt' was calling 'npm run format', but that
script did not exist yet. Also, formatting was only handled through
pre-commit, so it was still possible for unformatted TypeScript code to
get merged if pre-commit was not installed locally.

This PR adds Biome as a TypeScript dev dependency, adds format scripts,
and makes the TypeScript lint step check formatting too.

Closes #842.

**Testing I did**

Ran locally:

- 'npm ci'
- 'npm run format:check'
- 'npm run format'
- 'npm run lint'
- 'npm run test'
- 'npm run build'

I also temporarily added badly formatted TypeScript and confirmed 'npm
run format:check' failed, then restored the file.

Author: AlexChakmakian

.github/workflows/autofix.yml

@@ -8,6 +8,28 @@ on:
 permissions: {}
 
 jobs:
+  ts-fmt:
+    name: Format TypeScript
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    if: |
+      github.event.action == 'opened' ||
+      github.event.action == 'synchronize' ||
+      github.event.action == 'reopened'
+    steps:
+      - name: Checkout sources
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        with: { persist-credentials: false }
+      - uses: taiki-e/install-action@7a79fe8c3a13344501c80d99cae481c1c9085912 # v2.81.10
+        with: { tool: 'just' }
+      - uses: ./.github/actions/mlt-setup-node
+      - name: Format TypeScript
+        run: just ts::fmt
+
+      - uses: autofix-ci/action@c5b2d67aa2274e7b5a18224e8171550871fc7e4a # v1.3.4
+        with: { commit-message: "chore: format TypeScript" }
+
   rust-fmt-toml:
     name: Format Cargo.toml
     runs-on: ubuntu-latest

ts/mod.just

@@ -33,6 +33,7 @@ install:
 # Run linting
 lint: install
     npm run lint
+    npm run format:check
 
 # Run tests
 test: install

ts/package-lock.json

@@ -16,7 +16,9 @@
   "scripts": {
     "build": "tsc",
     "test": "vitest run --coverage --coverage.reportOnFailure",
-    "lint": "eslint"
+    "lint": "eslint",
+    "format": "biome format --write ./src",
+    "format:check": "biome format ./src"
   },
   "repository": {
     "type": "git",
@@ -26,6 +28,7 @@
     "url": "https://github.com/maplibre/maplibre-tile-spec/issues"
   },
   "devDependencies": {
+    "@biomejs/biome": "^2.4.16",
     "@eslint/js": "^10.0.1",
     "@mapbox/vector-tile": "^2.0.4",
     "@maplibre/maplibre-gl-style-spec": "^24.7.0",