feat: Add password hash generation scripts

- Add simple hash-password script for quick hash generation
- Add interactive generate-password script with hidden input
- Include password validation and requirements display
- Add npm scripts for easy execution
- Create comprehensive PASSWORD_GENERATION.md guide
- Use existing bcrypt infrastructure with 12 salt rounds

Usage:
  npm run hash-password YourPassword123\!
  npm run generate-password (interactive)

This solves the issue where bcrypt command line tools
don't work properly for generating compatible hashes.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

backend/package.json

@@ -9,7 +9,9 @@
     "dev:node": "node --watch src/app.js",
     "test": "jest --coverage",
     "lint": "eslint src/",
-    "lint:fix": "eslint src/ --fix"
+    "lint:fix": "eslint src/ --fix",
+    "hash-password": "node scripts/hash-password.js",
+    "generate-password": "node generate-password.js"
   },
   "keywords": ["minio", "api", "backend"],
   "author": "",