Use PSR-3 Logger instead of custom solution

[Greg0]

Summary

Replace the custom logger implementation with PSR-3 compliant logging interfaces, bringing the PHP SDK in line with established PHP logging standards and improving interoperability with existing logging solutions.

What Changed

Core Changes

• PSR-3 Compliance: Logger now implements Psr\Log\LoggerInterface and uses LoggerTrait
• Standard Log Levels: Migrated from custom log levels (warn, error, etc.) to PSR-3 standard levels (LogLevel::WARNING, LogLevel::ERROR, etc.)
• Improved Error Context: Enhanced error logging with proper exception context and structured data

Dependencies

• Added psr/log ^2.0: Core PSR-3 logging interface dependency
• Backward Compatible: Uses PSR-3 v2.0 for broader PHP version compatibility

API Updates

• Method Names: Updated warn() calls to warning() throughout codebase
• Type Hints: Added proper LoggerInterface type hints across all classes
• Context Structure: Improved logging context with consistent exception handling

Documentation

• Updated README: Refreshed logging section to reference PSR-3 standard

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No breaking changes for basic usage. The SDK maintains its existing logging behavior by default, but now accepts any PSR-3 compliant logger:

This change positions the Featurevisor PHP SDK as a more mature, standards-compliant library that integrates seamlessly with the broader PHP ecosystem.

[fahad19]

amazing! all tests are passing! 🚀

I will take a look tomorrow (Sunday) one more time aim for merge and release. thanks a lot!

[Greg0]

Please hold on with merging that PR. I would like to add one more thing:

• get rid of echoes in default logger handler. In PHP it's not good practice to echo things, it can corrupt application output that uses library. I assume that intention was to put logs into terminal. If so STDOUT is the right way.

[Greg0]

@fahad19 I've made changes I mentioned above. Few test cases were deleted due to untestable STDOUT stream. Working of that solution is delivered by language itself.

[fahad19]

will wait for your green light here before going for the merge.

[Greg0]

Rebased. IMO can be merged

[fahad19]

landed in v0.3.0: https://github.com/featurevisor/featurevisor-php/releases/tag/v0.3.0

thanks a lot, @Greg0!

once you feel it's time, would be great to also update the example PHP app here to new users can see real world example of latest SDK being used in an app: https://github.com/featurevisor/featurevisor-example-php