Add supplied post images to two posts and to the blog overview cards

- blog/posts/odoo-19-to-20-invoice-migration-with-n8n-and-mcp.html: in-post image
  much.png + og:image
- blog/posts/track-the-oca-modules-you-actually-use.html: in-post image
  oca_module_status.png + og:image
- blog/index.json: optional "image" key on those two entries only (text splice)
- script.js: renderBlog() draws .blog-thumb only when the entry carries an image
- style.css: .blog-thumb rule
- sitemap.xml: lastmod 2026-10-24 for the invoice-migration post

Built by profile webmaster (run 20261024_094206_5c4f28, verified PROBLEMS: 0 /
node --check OK); committed by olchi after that run died on an OpenRouter 402.

blog/index.json

@@ -6,7 +6,8 @@
       "area": "tips",
       "headline": "Track the OCA Modules You Actually Use — Without Refreshing GitHub Every Day",
       "teaser": "Every new Odoo release starts the same routine. You install the latest version, open a browser, and begin clicking throu",
-      "link": "blog/posts/track-the-oca-modules-you-actually-use.html"
+      "link": "blog/posts/track-the-oca-modules-you-actually-use.html",
+      "image": "https://image.office.odoo4projects.com/img/oca_module_status.png"
     },
     {
       "id": "odoo-19-to-20-invoice-migration-with-n8n-and-mcp",
@@ -14,7 +15,8 @@
       "area": "tips",
       "headline": "This is how i updated my Invoices from Odoo 19 to Odoo 20 with n8n and much MCP",
       "teaser": "Copying invoices from one Odoo instance to another by hand is the kind of task that looks small until you are on invoice",
-      "link": "blog/posts/odoo-19-to-20-invoice-migration-with-n8n-and-mcp.html"
+      "link": "blog/posts/odoo-19-to-20-invoice-migration-with-n8n-and-mcp.html",
+      "image": "https://image.office.odoo4projects.com/img/much.png"
     },
     {
       "id": "6-tips-to-leverage-the-latest-odoo-management-app-update",