[FIX] snailmail: fix follow-up reports layout for snailmails

Follow-up reports were previously not handled by the commit fixing
invoices. This commit aims to fix that.

closes odoo/odoo#107770

X-original-commit: 768cfbe0
Signed-off-by: Florian Daloze (fda) <fda@odoo.com>
Signed-off-by: Solan Delvenne (sode) <sode@odoo.com>

addons/snailmail/static/src/js/snailmail_external_layout.js

 // Change address font-size if needed
 document.addEventListener('DOMContentLoaded', function (evt) {
     var recipientAddress = document.querySelector(".address.row > div[name='address'] > address");
+    let baseSize = 120;
+    if (!recipientAddress) {
+        recipientAddress = document.querySelector("div .row.fallback_header > div.col-5.offset-7 > div:first-child");
+    }
     var style = window.getComputedStyle(recipientAddress, null); 
     var height = parseFloat(style.getPropertyValue('height'));
     var fontSize = parseFloat(style.getPropertyValue('font-size'));
-    recipientAddress.style.fontSize = (130 / (height / fontSize)) + 'px';
+    recipientAddress.style.fontSize = (baseSize / (height / fontSize)) + 'px';
 });

addons/snailmail/static/src/scss/snailmail_external_layout_asset.scss

@@ -52,3 +52,28 @@ div .address.row > div[name="address"] {
 		max-height: 33mm;
     }
 }
+
+/* Follow-up Letters */
+div .pt-5:empty {
+    display: none;
+}
+
+div .row.fallback_header {
+    margin-top: -4mm !important;
+    height: 68mm !important;
+    width: 117% !important;
+    > div .col-5.offset-7 {
+        background-color: #ffffff;
+        margin-left: 48.5% !important;
+        position: relative !important;
+        > div:first-child {
+            width: 100%;
+            padding-left: 2mm !important;
+            height: 33mm;
+            max-height: 33mm !important;
+            line-height: 1.1em;
+            position: absolute;
+            bottom: 0;
+        }
+    }
+}