Fix JsonLd generate() to respect the $minify parameter

[RohithVangalla1]

Summary

The generate() method in JsonLd and JsonLdMulti accepted a $minify parameter
but completely ignored it — JSON-LD output was always minified.

Fix

• JsonLd::generate(): When $minify is false (default), adds JSON_PRETTY_PRINT
  flag for readable output during development
• JsonLdMulti::generate(): Passes $minify through to individual JsonLd instances
  (was previously hardcoded without the parameter)

Before

// $minify = false, but output is still compact:
$jsonLd->generate(false);
// <script type="application/ld+json">{"@context":"https://schema.org","@type":"Organization","name":"Example"}</script>

## After
// $minify = false → pretty-printed:
$jsonLd->generate(false);
// <script type="application/ld+json">{
//     "@context": "https://schema.org",
//     "@type": "Organization",
//     "name": "Example"
// }</script>

// $minify = true → compact (unchanged):
$jsonLd->generate(true);
// <script type="application/ld+json">{"@context":"https://schema.org","@type":"Organization","name":"Example"}</script>


| Q             | A
| ------------- | ---
| Is bugfix?    | ✔️
| Fixed issues  | comma-separated list of tickets # fixed by the PR, if any