This PR fixes the PHPDoc type for DataCollector::getPlatformCalls().

Problem

The PlatformCallData type (defined in TraceablePlatform) declares result: DeferredResult. However, after DataCollector::lateCollect() processes the data through awaitCallResults(), the result field is transformed to string|iterable|object|null and a metadata field is added.

This causes PHPStan errors when testing code that accesses the transformed data (e.g., assertNull($dataCollector->getPlatformCalls()[0]['result'])).

Solution

Introduce a new PHPDoc type CollectedPlatformCallData that accurately describes the data returned by getPlatformCalls() after transformation:

@phpstan-type CollectedPlatformCallData array{
    model: string,
    input: array<mixed>|string|object,
    options: array<string, mixed>,
    result: string|iterable<mixed>|object|null,
    metadata: Metadata,
}