Fix description line breaks and disabled-field readability

Ticket descriptions are plain text — renderDescriptionView() now always
uses nl2br instead of parseMarkdown(), preventing markdown from mangling
single newlines into run-on paragraphs.

Override base.css opacity:0.45 on disabled .editable-metadata selects
(Priority, Category, Type) so they remain legible at full contrast on
dark/OLED screens in read mode.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

assets/js/ticket.js

@@ -88,9 +88,8 @@ function renderDescriptionView() {
     var raw = textarea.value || '';
     if (!raw.trim()) {
         viewDiv.innerHTML = '<p class="lt-text-muted lt-text-sm"><em>No description provided.</em></p>';
-    } else if (typeof parseMarkdown === 'function') {
-        viewDiv.innerHTML = parseMarkdown(raw);
     } else {
+        // Ticket descriptions are plain text — preserve line breaks, never run markdown.
         viewDiv.innerHTML = lt.escHtml(raw).replace(/\n/g, '<br>');
     }
 }