Refactor blocks architecture to modular approach

- Restore "1/2, 1/2" layout for flexible column combinations
- Simplify beforeafter block: remove toggle and text field, keep only image comparison
- Create new video block with URL support (YouTube/Vimeo/direct files)
- Create horizontal-gallery block for scrollable image galleries
- Add H4 heading level support
- All blocks now modular: combine with text blocks in 2-column layouts

Blocks available:
- Text, Heading (h2-h4), Image, Video
- Before/After comparison (no text)
- Horizontal gallery (with text below)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

site/plugins/beforeafter/index.js

@@ -1 +1 @@
-(function(){"use strict";function m(a,e,t,i,s,c,r,n){var o=typeof a=="function"?a.options:a;return e&&(o.render=e,o.staticRenderFns=t,o._compiled=!0),o._scopeId="data-v-"+c,{exports:a,options:o}}const l={__name:"BeforeAfterBlock",props:{content:Object},setup(a){const e=a,t=Vue.computed(()=>{var r,n;return((r=e.content)==null?void 0:r.isbeforeafter)===!0||((n=e.content)==null?void 0:n.isbeforeafter)==="true"}),i=Vue.computed(()=>{var n;if(!((n=e.content)!=null&&n.image)||!e.content.image.length)return null;const r=e.content.image[0];return(r==null?void 0:r.url)||null}),s=Vue.computed(()=>{var n;if(!((n=e.content)!=null&&n.imagebefore)||!e.content.imagebefore.length)return null;const r=e.content.imagebefore[0];return(r==null?void 0:r.url)||null}),c=Vue.computed(()=>{var n;if(!((n=e.content)!=null&&n.imageafter)||!e.content.imageafter.length)return null;const r=e.content.imageafter[0];return(r==null?void 0:r.url)||null});return{__sfc:!0,props:e,isBeforeAfter:t,imageUrl:i,imageBeforeUrl:s,imageAfterUrl:c}}};var _=function(){var e=this,t=e._self._c,i=e._self._setupProxy;return t("div",{staticClass:"imagetext-preview",on:{click:function(s){return e.$emit("open")}}},[t("div",{staticClass:"imagetext-preview__container"},[t("div",{staticClass:"imagetext-preview__media"},[i.isBeforeAfter&&(i.imageBeforeUrl||i.imageAfterUrl)?t("div",{staticClass:"imagetext-preview__slider"},[i.imageAfterUrl?t("img",{staticClass:"imagetext-preview__image imagetext-preview__image--after",attrs:{src:i.imageAfterUrl,alt:"Après"}}):e._e(),i.imageBeforeUrl?t("img",{staticClass:"imagetext-preview__image imagetext-preview__image--before",attrs:{src:i.imageBeforeUrl,alt:"Avant"}}):e._e(),i.imageBeforeUrl&&i.imageAfterUrl?t("div",{staticClass:"imagetext-preview__divider"}):e._e()]):!i.isBeforeAfter&&i.imageUrl?t("img",{staticClass:"imagetext-preview__single-image",attrs:{src:i.imageUrl,alt:"Image"}}):t("div",{staticClass:"imagetext-preview__empty-media"},[e._v(" Aucune image ")]),e.content.caption?t("p",{staticClass:"imagetext-preview__caption"},[e._v(" "+e._s(e.content.caption)+" ")]):e._e()]),t("div",{staticClass:"imagetext-preview__text"},[e.content.text?t("div",{domProps:{innerHTML:e._s(e.content.text)}}):t("div",{staticClass:"imagetext-preview__empty-text"},[e._v(" Aucun texte ")])])])])},f=[],g=m(l,_,f,!1,null,"caec09ec");const u=g.exports;window.panel.plugin("index/beforeafter",{blocks:{beforeafter:u}})})();
+(function(){"use strict";function f(a,e,r,t,n,o,u,p){var i=typeof a=="function"?a.options:a;return e&&(i.render=e,i.staticRenderFns=r,i._compiled=!0),i._scopeId="data-v-"+o,{exports:a,options:i}}const s={__name:"BeforeAfterBlock",props:{content:Object},setup(a){const e=a,r=Vue.computed(()=>{var o;if(!((o=e.content)!=null&&o.imagebefore)||!e.content.imagebefore.length)return null;const n=e.content.imagebefore[0];return(n==null?void 0:n.url)||null}),t=Vue.computed(()=>{var o;if(!((o=e.content)!=null&&o.imageafter)||!e.content.imageafter.length)return null;const n=e.content.imageafter[0];return(n==null?void 0:n.url)||null});return{__sfc:!0,props:e,imageBeforeUrl:r,imageAfterUrl:t}}};var c=function(){var e=this,r=e._self._c,t=e._self._setupProxy;return r("div",{staticClass:"beforeafter-preview",on:{click:function(n){return e.$emit("open")}}},[t.imageBeforeUrl||t.imageAfterUrl?r("div",{staticClass:"beforeafter-preview__slider"},[t.imageAfterUrl?r("img",{staticClass:"beforeafter-preview__image beforeafter-preview__image--after",attrs:{src:t.imageAfterUrl,alt:"Après"}}):e._e(),t.imageBeforeUrl?r("img",{staticClass:"beforeafter-preview__image beforeafter-preview__image--before",attrs:{src:t.imageBeforeUrl,alt:"Avant"}}):e._e(),t.imageBeforeUrl&&t.imageAfterUrl?r("div",{staticClass:"beforeafter-preview__divider"}):e._e()]):e._e(),e.content.caption?r("p",{staticClass:"beforeafter-preview__caption"},[e._v(" "+e._s(e.content.caption)+" ")]):e._e(),!t.imageBeforeUrl&&!t.imageAfterUrl?r("div",{staticClass:"beforeafter-preview__empty"},[e._v(" Cliquer pour ajouter des images ")]):e._e()])},l=[],_=f(s,c,l,!1,null,"7994b7b1");const m=_.exports;window.panel.plugin("index/beforeafter",{blocks:{beforeafter:m}})})();