Feature: #107359 - Introduce Fluid page meta ViewHelper

Description

A new Fluid ViewHelper <f:page.meta> has been introduced to allow setting meta tags directly from Fluid templates using TYPO3's MetaTagManager API.

This is especially useful for Extbase plugins that need to set meta tags in their detail views without having to implement custom meta tag handling.

In addition, frontend developers do not need to write custom TypoScript anymore but can use Fluid directly.

EXT:my_extension/Resources/Private/Templates/Item/Show.html

<f:page.meta property="description">{item.description}</f:page.meta>
<f:page.meta property="og:title">{item.title}</f:page.meta>
<f:page.meta property="og:type">article</f:page.meta>

<h1>{item.title}</h1>
<p>{item.description}</p>

The ViewHelper supports all features of the MetaTagManager API:

OpenGraph and Twitter / X Card meta tags:

<f:page.meta property="og:title">My Article Title</f:page.meta>
<f:page.meta property="og:description">Article description</f:page.meta>
<f:page.meta property="twitter:card">summary_large_image</f:page.meta>

Sub-properties for complex meta tags:

<f:page.meta property="og:image"
             subProperties="{width: 1200, height: 630, alt: 'Article image'}">{item.image.url}</f:page.meta>

Custom meta tag types:

<f:page.meta property="author" type="name">John Doe</f:page.meta>
<f:page.meta property="robots" type="name">index, follow</f:page.meta>

Replacing existing meta tags:

<f:page.meta property="description" replace="true">Override any existing description</f:page.meta>

ViewHelper Arguments

property (required): The meta property name (e.g. "description", "og:title")
type (optional): The meta type attribute ("name", "property", "http-equiv"). If not set, the appropriate MetaTagManager will determine the type automatically
subProperties (optional): Array of sub-properties for complex meta tags
replace (optional): Boolean to replace existing meta tags with the same property (default: false)

Impact

Extension developers can now easily set meta tags from their Fluid templates without needing to use the MetaTagManager API directly in PHP code. This simplifies the implementation of SEO-optimized pages in Extbase plugins, especially for detail views where meta tags should reflect the displayed record.

The ViewHelper integrates seamlessly with TYPO3's existing MetaTagManager system and respects all configured meta tag managers and their priorities.