fix(plating): CoC + invoice PDFs render full content

Three reported PDF bugs from the customer-facing email package:

1. Invoice body was empty — Odoo 19 sets display_type='product' on
   regular invoice/SO lines (was empty string in 18.0). Both
   report_fp_invoice.xml and report_fp_sale.xml only matched
   `not line.display_type`, so every product line was skipped.
   Fixed both portrait + landscape variants to also match
   display_type == 'product'.

2. CoC PDF was a bare 30 KB header — _fp_generate_cert_pdf was
   rendering action_report_coc, which is bound to portal_job and
   has minimal content. Rewrote to use the rich fp.certificate-bound
   report (action_report_coc_en / action_report_coc_fr based on
   cert.partner_id.lang) and slugged the filename to
   CoC-<Customer>-<CertName>.pdf so the email attachment reads
   nicely instead of CERT-00123.pdf.

3. Thickness cert was an exact duplicate of the CoC — the CoC
   template already embeds thickness readings. Skip thickness cert
   creation entirely when the customer also wants CoC; only create
   a standalone thickness cert when the customer opted out of CoC.

Also: dispatcher in fp_notification_template now prefers
portal_job.coc_attachment_id (the rich one we just generated) and
falls back to rendering action_report_coc_en against fp.certificate
by partner.lang — never the bare portal-job report.

Versions bumped: bridge_mrp 19.0.6.0.0, notifications 19.0.4.0.0,
reports 19.0.4.0.0.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

fusion_plating/fusion_plating_notifications/__manifest__.py

@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating — Notifications',
-    'version': '19.0.3.0.0',
+    'version': '19.0.4.0.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Auto-email notifications at workflow milestones with configurable templates, PDF attachments, and audit log.',
     'author': 'Nexa Systems Inc.',