fix: prevent horizontal page scroll on post detail page

- markdown.css: .prose table gets display:block + overflow-x:auto so
  wide tables scroll inside their own box instead of stretching the page
  (post 2970 had a 1076px table overflowing 390px mobile and 1440px desktop)
- td gets word-break:break-word + overflow-wrap:anywhere for long URLs
- post_detail.html: .post-actions max-width:100% so Listen/Edit/Share/Delete
  buttons wrap inside the container on narrow screens

links/templates/links/post_detail.html

@@ -419,7 +419,7 @@
     }
     .post-header-row { display: flex; flex-wrap: wrap; align-items: flex-start; justify-content: space-between; gap: 0.85rem; margin-bottom: 1.1rem; }
     .post-title { font-size: clamp(1.5rem, 3.4vw, 2.1rem); font-weight: 700; letter-spacing: -0.02em; line-height: 1.2; flex: 1 1 16rem; min-width: 0; color: var(--apple-text); }
-    .post-actions { display: flex; align-items: center; gap: 0.5rem; flex-shrink: 0; flex-wrap: wrap; }
+    .post-actions { display: flex; align-items: center; gap: 0.5rem; flex-shrink: 0; flex-wrap: wrap; max-width: 100%; }
     .post-meta { display: flex; flex-direction: column; gap: 0.85rem; margin-bottom: 1.25rem; }
     .post-summary { position: relative; padding-left: 1rem; border-left: 3px solid rgba(0, 113, 227, 0.35); }
     .post-summary p { font-size: 1.08rem; color: var(--apple-gray); font-style: italic; margin: 0; }

static/css/markdown.css

@@ -81,9 +81,12 @@
     margin: 1.25em 0;
 }
 .prose table {
+    display: block;
     width: 100%;
+    overflow-x: auto;
     border-collapse: collapse;
     margin: 2em 0;
+    -webkit-overflow-scrolling: touch;
 }
 .prose table th {
     background-color: #f3f4f6;
@@ -95,4 +98,6 @@
 .prose table td {
     padding: 0.5em;
     border: 1px solid #e5e7eb;
+    word-break: break-word;
+    overflow-wrap: anywhere;
 }