Add collapsible manual panel to give progress pane more room

Toggle button (top-left of column, always same position) collapses the
manual panel from 16em to 2em with a CSS transition; state persists in
localStorage across reloads.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SH2D4LRuCnhLSzoYerAfJX

web/style.css

@@ -182,6 +182,33 @@ header#connection-bar {
     gap: 1.5em;
     align-items: start;
     margin-top: 1em;
+    transition: grid-template-columns 0.2s ease;
+}
+#layout.manual-collapsed {
+    grid-template-columns: 2em auto 1fr;
+}
+
+/* --- Manual column collapse --- */
+
+#col-manual {
+    display: flex;
+    flex-direction: column;
+    overflow: hidden;
+}
+#btn-manual-toggle {
+    align-self: flex-start;
+    width: 2em;
+    height: 2em;
+    padding: 0;
+    font-size: 0.9em;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    flex-shrink: 0;
+    margin-bottom: 0.4em;
+}
+#layout.manual-collapsed #manual-panels {
+    display: none;
 }
 
 #col-progress { overflow-y: auto; }