fix(ui): a described session tab shows just the description (#232)

Reported by @mtiller.

A session named `w2-foo-bar: some description` rendered both halves on the tab, so
the generated id ate the width that the part the user actually chose needed. The
tab now shows the description alone and the `w<n>-<case>` id moves to the tooltip,
where it stays available without being read every time. It is still shown in the
session settings modal. Undescribed tabs are unchanged.

`aria-label` deliberately keeps the FULL name, so screen readers still get the id.

Also fixes a re-render loop this exposed: the incremental update compared
`nameEl.textContent` against the full name, which for a described tab never
matched, so those tabs re-rendered on every pass. The compare now targets the
display label.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/web/public/app.js

@@ -3438,14 +3438,19 @@ class CodemanApp {
           statusEl.className = `tab-status ${status}`;
         }
 
-        // Update name if changed
+        // Update name if changed. #232: a description (the `: suffix` part of the
+        // name) is the whole tab label; the generated id lives in the tooltip. The
+        // compare targets the DISPLAY text, or a described tab would re-render on
+        // every pass (textContent never equals the full name there).
         const nameEl = tab.querySelector('.tab-name');
-        if (nameEl && nameEl.textContent !== name) {
+        if (nameEl) {
           const _p = parseSessionPrefix(name);
-          if (_p && _p.suffix) {
-            nameEl.innerHTML = '<span class="tab-prefix">' + escapeHtml(_p.prefix) + '</span><span class="tab-suffix">: ' + escapeHtml(_p.suffix) + '</span>';
-          } else {
-            nameEl.textContent = name;
+          const _label = _p && _p.suffix ? _p.suffix : name;
+          if (nameEl.textContent !== _label) {
+            nameEl.textContent = _label;
+            tab.title = _p && _p.suffix
+              ? (session.workingDir ? `${_p.prefix} (${session.workingDir})` : _p.prefix)
+              : (session.workingDir || '');
           }
         }
 
@@ -3617,14 +3622,23 @@ class CodemanApp {
       const tallTabsEnabled = this._tallTabsEnabled ?? false;
       const showFolder = tallTabsEnabled && session.name && folderName && folderName !== name;
 
-      parts.push(`<div class="session-tab ${isActive ? 'active' : ''}${alertClass}${loadState ? ' tab-loading' : ''}" data-id="${id}" data-color="${color}" ${loadState ? `data-load-phase="${escapeHtml(loadState.phase)}"` : ''} onclick="app.handleSessionTabClick(event, ${escapeHtml(JSON.stringify(id))})" oncontextmenu="event.preventDefault(); app.startInlineRename(${escapeHtml(JSON.stringify(id))})" tabindex="0" role="tab" aria-selected="${isActive ? 'true' : 'false'}" aria-busy="${loadState ? 'true' : 'false'}" aria-label="${escapeHtml(name)} session" ${session.workingDir ? `title="${escapeHtml(session.workingDir)}"` : ''}>
+      // #232: a session with a description (the `: suffix` part of its name) shows
+      // JUST the description on the tab; the generated w<n>-<case> id moves to the
+      // tooltip and stays visible in the session settings modal.
+      const parsedName = parseSessionPrefix(name);
+      const tabLabel = parsedName && parsedName.suffix ? parsedName.suffix : name;
+      const tabTooltip = parsedName && parsedName.suffix
+        ? (session.workingDir ? `${parsedName.prefix} (${session.workingDir})` : parsedName.prefix)
+        : (session.workingDir || '');
+
+      parts.push(`<div class="session-tab ${isActive ? 'active' : ''}${alertClass}${loadState ? ' tab-loading' : ''}" data-id="${id}" data-color="${color}" ${loadState ? `data-load-phase="${escapeHtml(loadState.phase)}"` : ''} onclick="app.handleSessionTabClick(event, ${escapeHtml(JSON.stringify(id))})" oncontextmenu="event.preventDefault(); app.startInlineRename(${escapeHtml(JSON.stringify(id))})" tabindex="0" role="tab" aria-selected="${isActive ? 'true' : 'false'}" aria-busy="${loadState ? 'true' : 'false'}" aria-label="${escapeHtml(name)} session" ${tabTooltip ? `title="${escapeHtml(tabTooltip)}"` : ''}>
           ${_tabIdx < 9 ? '<span class="tab-number">' + (_tabIdx + 1) + '</span>' : ''}
           ${loadState ? '<span class="tab-load-spinner" aria-hidden="true"></span>' : ''}
           <span class="tab-status ${status}" aria-hidden="true"></span>
           <span class="tab-info">
             <span class="tab-name-row">
               ${mode === 'shell' ? '<span class="tab-mode shell" aria-hidden="true">sh</span>' : mode === 'opencode' ? '<span class="tab-mode opencode" aria-hidden="true">oc</span>' : mode === 'codex' ? '<span class="tab-mode codex" aria-hidden="true">cx</span>' : mode === 'gemini' ? '<span class="tab-mode gemini" aria-hidden="true">gm</span>' : mode === 'antigravity' ? '<span class="tab-mode antigravity" aria-hidden="true">ag</span>' : ''}
-              <span class="tab-name" data-session-id="${id}">${(() => { const p = parseSessionPrefix(name); return p && p.suffix ? '<span class="tab-prefix">' + escapeHtml(p.prefix) + '</span><span class="tab-suffix">: ' + escapeHtml(p.suffix) + '</span>' : escapeHtml(name); })()}</span>
+              <span class="tab-name" data-session-id="${id}">${escapeHtml(tabLabel)}</span>
               <span class="tab-detached-badge" aria-hidden="true">detached</span>
             </span>
             ${showFolder ? `<span class="tab-folder">\u{1F4C1} ${escapeHtml(folderName)}</span>` : ''}

src/web/public/styles.css

@@ -1383,15 +1383,6 @@ html[data-line-anim="packet"] .connection-line.line-enter {
   text-overflow: ellipsis;
 }
 
-.session-tab .tab-prefix {
-  color: var(--text-muted);
-}
-
-.session-tab .tab-suffix {
-  color: var(--text);
-  font-weight: 500;
-}
-
 /* Tab folder path — hidden by default, shown via .tabs-show-folder on container */
 .session-tab .tab-folder {
   font-size: 0.6rem;