fix: getCasts() to include casts() method for non-incrementing models

[binaryfire]

Summary

The getCasts() method in HasAttributes was only calling $this->casts() for incrementing models. For non-incrementing models (those using HasUuids or HasUlids), only the $casts property was returned, ignoring the casts() method entirely.

The Bug

public function getCasts(): array
{
    // ...cache check...

    if ($this->getIncrementing()) {
        // ✅ Incrementing: calls both property AND method
        return ... = array_merge([...], $this->casts, $this->casts());
    }

    // ❌ Non-incrementing: only returns property, ignores method!
    return ... = $this->casts;
}

Impact

Any model using HasUuids or HasUlids that defines casts via the casts() method (Laravel's modern approach) would have those casts ignored. This causes issues like:

• Arrays not being JSON-encoded when saved to database
• Dates not being cast to Carbon instances
• Enums not being properly cast

The Fix

return static::$castsCache[static::class] = array_merge($this->casts, $this->casts());

Now the non-incrementing branch also merges both the property and method, matching the behavior of the incrementing branch.

Test Plan

• Added HasAttributesTest with 3 test cases:
  • testGetCastsIncludesCastsMethodForIncrementingModels - existing behavior works
  • testGetCastsIncludesCastsMethodForNonIncrementingModels - UUID models get casts() method
  • testGetCastsMergesPropertyAndMethodForNonIncrementingModels - both property and method are merged