[#3] Install & configure lint-staged

This runs our linters & formatters on just the files that have changed.

.husky/pre-commit

@@ -1 +1 @@
-npm run format
+ddev exec npx lint-staged

lint-staged.config.js

@@ -0,0 +1,14 @@
+/**
+ * This runs within the DDEV container
+ * We have access to the appropriate PHP & Composer versions
+ */
+export default {
+  '**/*.php': [
+    './vendor/bin/ecs check --ansi --fix',
+    './vendor/bin/phpstan analyse --memory-limit=1G',
+  ],
+  '*.{js,jsx,ts,tsx}': ['eslint --fix', 'prettier --ignore-unknown --write'],
+  // Negate the JS files above so there isn't a race condition
+  // https://github.com/lint-staged/lint-staged?tab=readme-ov-file#task-concurrency
+  '!(*.js|*.jsx|*.ts|*.tsx)': 'prettier --ignore-unknown --write',
+}