chore: add husky and format:fix script (#535)

* chore: add husky and format:fix script

* docs: initialize empty CHANGELOG.md

Placeholder — release notes will be populated at merge time.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

package.json

@@ -11,7 +11,9 @@
     "auth": "tsx src/whatsapp-auth.ts",
     "typecheck": "tsc --noEmit",
     "format": "prettier --write \"src/**/*.ts\"",
+    "format:fix": "prettier --write \"src/**/*.ts\"",
     "format:check": "prettier --check \"src/**/*.ts\"",
+    "prepare": "husky",
     "setup": "tsx setup/index.ts",
     "test": "vitest run",
     "test:watch": "vitest"
@@ -32,6 +34,7 @@
     "@types/node": "^22.10.0",
     "@types/qrcode-terminal": "^0.12.2",
     "@vitest/coverage-v8": "^4.0.18",
+    "husky": "^9.1.7",
     "prettier": "^3.8.1",
     "tsx": "^4.19.0",
     "typescript": "^5.7.0",