Resolve Composer Dependencies and Build Directory Issue

[rikgirbes]

Description:
Following related discussions in other issues (#5 #4 #3), I've observed that the build directory contains some Composer packages that are committed to the repository. This seems to be done as a workaround to avoid dependency issues. However, it's contradictory that the dependencies are still listed under the "require" section in composer.json.

This approach doesn't make sense, as it introduces unnecessary redundancy and potential confusion.

Proposed Solutions

1. Best Practice: Update all the packages to their latest versions, solve dependency issues, and remove the build directory entirely. This ensures we rely solely on Composer for dependency management.
2. Alternative: Move the problematic dependencies to the "require-dev" section in composer.json if they are only needed for development or testing purposes.

Recommendations
Since this is a new SDK, we should prioritize modern practices:

• Update the dependencies to their latest versions.
• Set the minimum PHP version to PHP 8.3.
• Avoid supporting legacy PHP versions or outdated Composer packages.

This approach will clean up the repository, eliminate unnecessary workarounds, and ensure better long-term maintainability.

Acceptance Criteria:

• Remove the build directory from version control.
• Update composer.json to require only necessary, modern dependencies.
• Set the minimum PHP version to 8.3.
• Verify the SDK builds and runs as expected without dependency issues.