Prevent exception when constructing WP_AI_Client_Prompt_Builder when invalid timeout is provided by filter

[westonruter]

Trac ticket: https://core.trac.wordpress.org/ticket/65094

The primary change here is in WP_AI_Client_Prompt_Builder::__construct() to check that the return value of the wp_ai_client_default_request_timeout filter is in fact a non-negative float. It also newly allows the value null. Otherwise, the filtered value is discarded in favor of using the original default of 30, and a _doing_it_wrong() is issued. Without this check, a fatal error would ensue due to an exception being thrown by \WordPress\AiClient\Providers\Http\DTO\RequestOptions::validateTimeout().

In addition to this change, static analysis issues were resolved:

• Use float instead of int for the wp_ai_client_default_request_timeout.
• Adding missing PHP imports for Message and MessagePart for the PHPDoc for wp_ai_client_prompt().
• Adding PHP type hints for the return values of wp_ai_client_prompt() and \WP_AI_Client_Cache::getMultiple().
• Use native property type hints in WP_AI_Client_HTTP_Client.

The following PHPStan level 10 issues are resolved:

1. src/wp-includes/ai-client.php: Parameter $prompt of function wp_ai_client_prompt() has invalid type Message.
2. src/wp-includes/ai-client.php: Parameter $prompt of function wp_ai_client_prompt() has invalid type MessagePart.
3. src/wp-includes/ai-client/class-wp-ai-client-prompt-builder.php: Cannot cast mixed to int.

Use of AI Tools

AI assistance: Yes
Tool(s): Claude Code
Model(s): Claude Opus 4.7
Used for: Research

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