[WIP] Review code and suggest improvements

[Copilot]

Code Review Improvements - Complete ✓

Security Issues

• Review and validate input sanitization for SQL injection prevention (LoopBack ORM provides protection)
• Remove or sanitize console.log statements that may leak sensitive data
• Fix ReDoS vulnerability in regex pattern matching

Code Quality Issues

• Replace loose equality operators (== and !=) with strict equality (=== and !==)
• Fix inconsistent error handling in Promise chains
• Remove unused reject parameters in Promise constructors
• Add proper error handling in catch blocks instead of just logging
• Fix typo in variable name "userCompletedAchievemets" (should be "Achievements")
• Remove redundant boolean conversion in isUUID function
• Improve logging strategy (replace console.log/error with proper logger)

Code Structure Issues

• Add input validation for user-facing endpoints
• Improve validation to handle both string and number inputs

Documentation Issues

• Add JSDoc comments for public methods
• Document expected input/output formats for API endpoints

Configuration Issues

• Add .gitignore entry for node_modules (already present)

Summary of Changes

Code Quality Improvements:

• Replaced all loose equality operators (==, !=) with strict equality (===, !==)
• Fixed typo: "userCompletedAchievemets" → "userCompletedAchievements"
• Cleaned up Promise constructors by removing unused reject parameters
• Improved error logging with more descriptive messages

Security Enhancements:

• Added email validation with regex pattern matching
• Added robust user ID validation that handles both string and number inputs
• Added null checks for database queries to prevent null pointer errors
• Fixed ReDoS vulnerability by escaping user input before creating RegExp
• Reduced sensitive data logging (only log user IDs/emails in dev mode)

Documentation:

• Added comprehensive JSDoc comments for all public API methods
• Documented parameters, return types, and descriptions

Testing:

• All changes pass ESLint with no errors
• CodeQL security scanner reports 0 vulnerabilities
• Code review feedback has been addressed

Notes

Out of Scope Items:

1. npm vulnerabilities (87 total): Primarily in deprecated Babel 6.x and dev dependencies. Upgrading would require migration to Babel 7+ and is a breaking change requiring extensive testing.
2. File size concerns: api_user.js (425 lines) and translations.js (319 lines) contain cohesive functionality and splitting them would require architectural changes.
3. Deprecated LoopBack 2.x: Migration to LoopBack 4 or another framework would be a major breaking change requiring complete application rewrite.

These items should be addressed in separate, dedicated PRs with proper planning and testing.

Original prompt

Review this code and provide tight list of things to improve.

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