Fixed 560px sidebar; divider moved to main

src/uwudash_mk3/static/styles.css

@@ -47,12 +47,12 @@ body {
 .sidebar {
   width: 220px;
   flex: 0 0 220px;
-  height: 100vh;
+  height: 560px;
+  max-height: 100vh;
   position: sticky;
   top: 0;
   overflow-y: auto;
   background: var(--panel);
-  border-right: 1px solid var(--border);
   display: flex;
   flex-direction: column;
   padding: 16px 12px;
@@ -119,7 +119,7 @@ body {
 .user-chip .btn { margin-left: auto; }
 
 /* ------------------------------------------------------------------- main */
-.main { flex: 1; display: flex; flex-direction: column; min-width: 0; }
+.main { flex: 1; display: flex; flex-direction: column; min-width: 0; border-left: 1px solid var(--border); }
 
 .viewer { flex: 1; display: flex; flex-direction: column; min-height: 0; }
 .viewer-bar {