Guard URL field against non-scalar values

[cbravobernal]

Description

The URL field's validate_value() and format_value() methods can receive a non-scalar value (for example an array) from a form submission, since the submitted value is not guaranteed to be a string. When that happens:

• validate_value() calls strpos( $value, '://' ), which raises a TypeError on PHP 8 when $value is an array.
• format_value() calls esc_url( $value ) (which internally calls ltrim()) when escape_html is true, raising a TypeError on an array.

A non-scalar value is never a valid URL, so the field should treat it as invalid/empty rather than raising a fatal TypeError. This PR adds a minimal type guard to both methods:

• validate_value(): a non-string value returns the existing "Value must be a valid URL" validation message.
• format_value(): a non-string value returns an empty string when escaping, matching how the field already treats an empty value.

Behavior for normal string values is unchanged.

This file is derived from an upstream plugin; the same change applies upstream.

Verification

• composer test:php — full suite green (2266 tests), including new regression tests test_validate_value_non_scalar and test_format_value_non_scalar_escaped.
• composer test:phpstan — clean (no errors).
• vendor/bin/phpcs on the changed field class and test file — clean (no new violations introduced).

Use of AI Tools

This change was authored by Claude Code under human direction. The human author reviewed and takes responsibility for the change.

🤖 Generated with Claude Code

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