feat: Include updated_at timestamp in UserCacheService cache key

[roncodes]

Description

This PR enhances the UserCacheService by incorporating the user's updated_at timestamp into the cache key generation. This change enables automatic cache busting when user data is modified, improving cache consistency and data freshness.

Changes Made

Core Changes

• UserCacheService.php
  • Updated getCacheKey() to accept User object and include updated_at timestamp in the key
  • Modified get(), put(), and invalidate() methods to accept User objects instead of just user IDs
  • Updated all log statements to use $user->uuid consistently

Controller Updates

• UserController.php
  • Updated current() method to pass the full $user object to cache service methods

Documentation Updates

• UserObserver.php - Added clarifying comments about automatic cache busting
• User.php - Added clarifying comments in assignSingleRole() method

Benefits

✅ Automatic cache invalidation - When user data changes, the updated_at timestamp changes, resulting in a new cache key
✅ Improved data consistency - Ensures stale data is never served from cache
✅ Aligns with existing patterns - Matches the generateETag() implementation which already uses updated_at
✅ Simplified cache management - Reduces reliance on explicit invalidation calls
✅ Better cache efficiency - Old cache entries expire naturally via TTL

Cache Key Format

Before: user:current:{userId}:{companyId}
After: user:current:{userUuid}:{companyId}:{updatedAtTimestamp}

Example: user:current:abc-123-def:company-456:1707619200

Testing Recommendations

• Verify cache key generation includes timestamp
• Test that updating a user creates a new cache entry
• Confirm old cache entries are not used after user updates
• Validate cache behavior across user role changes

Backward Compatibility

This change is backward compatible. Old cache keys will naturally expire based on the configured TTL (default 15 minutes). No migration or manual cache clearing is required.

Related

Implements the technical plan for improving user cache management by leveraging timestamp-based cache keys.