seo: use params.author and add ImageObject schema to figures

Move author configuration to [params] for modern Hugo compatibility
and update the head partial. Enhance the figure shortcode with
structured data, async decoding, and improved alt/caption handling.

This improves SEO and future-proofs author references across the site.

Author: pH-7

hugo.toml

@@ -15,6 +15,7 @@ enableRobotsTXT = true
   blog = "/blog/:slug/"
 
 [params]
+  author = "Pierre-Henry Soria"
   description = "CTO insights, software architecture, engineering leadership, and product strategy. Lessons in building, scaling, and leading teams, with a focus on technical decision-making, business impact, and AI-driven product development."
   keywords = ["CTO", "software architecture", "engineering leadership", "product strategy", "AI engineering", "system design", "business impact", "Pierre-Henry Soria"]
   title = "Pierre-Henry Soria – Engineering Leadership & Product Strategy"

layouts/partials/head.html

@@ -1,7 +1,7 @@
 {{- /* Enhanced SEO and social meta tags */ -}}
 <title>{{ if .Title }}{{ .Title }} | {{ end }}{{ .Site.Title }}</title>
 <meta name="description" content="{{ with .Description }}{{ . }}{{ else }}{{ .Site.Params.description }}{{ end }}">
-<meta name="author" content="{{ .Site.Author }}">
+<meta name="author" content="{{ .Site.Params.author }}">
 
 <!-- Open Graph -->
 <meta property="og:title" content="{{ if .Title }}{{ .Title }} | {{ end }}{{ .Site.Title }}">

layouts/shortcodes/figure.html

@@ -1,10 +1,13 @@
-<figure>
+{{- $alt := .Get "alt" | default (.Get "title") | default .Page.Title -}}
+{{- $title := .Get "title" | default .Page.Title -}}
+<figure itemscope itemtype="https://schema.org/ImageObject">
   {{- if .Get "link" -}}
     <a href="{{ .Get "link" }}" target="_blank" rel="noopener">
   {{- end -}}
-  <img src="{{ .Get "src" }}" alt="{{ .Get "alt" }}" title="{{ .Get "title" }}" loading="lazy" />
+  <img src="{{ .Get "src" }}" alt="{{ $alt }}" title="{{ $title }}" loading="lazy" decoding="async" itemprop="contentUrl" />
+  <meta itemprop="name" content="{{ $title }}" />
   {{- if .Get "link" -}}</a>{{- end -}}
   {{- if .Get "caption" -}}
-    <figcaption class="image-caption">{{ .Get "caption" }}</figcaption>
+    <figcaption class="image-caption" itemprop="caption">{{ .Get "caption" | markdownify }}</figcaption>
   {{- end -}}
 </figure>