fix active tab hidden in the tab strip's horizontal overflow

render() rebuilds #tab-list with innerHTML = '', which clamps scrollLeft back
to 0, so with enough tabs to overflow the strip the active one silently landed
off-screen — most visibly right after clicking a project, since setActiveProject
emits project-changed and the tab bar re-renders on it.

Capture the offset before the wipe, restore it after the rebuild, then scroll
the active tab into view. Restoring it is what keeps unrelated re-renders
(unread transitions, share state, layout) from moving the strip at all: with
the offset back in place, inline: 'nearest' is a no-op while the tab is already
fully visible. The active element is captured in the existing append loop
rather than re-queried, since render() already computes isActive.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Author: elirantutia

src/renderer/components/tab-bar/tab-list.ts

@@ -293,10 +293,13 @@ function showTabContextMenu(x: number, y: number, project: ProjectRecord, sessio
 
 export function render(): void {
   if (tabListEl.querySelector('.tab-name input')) return;
+  // Read before the wipe below clamps it to 0.
+  const prevScrollLeft = tabListEl.scrollLeft;
   tabListEl.innerHTML = '';
   const project = appState.activeProject;
   if (!project) return;
 
+  let activeTab: HTMLElement | null = null;
   for (const session of project.sessions) {
     const tab = document.createElement('div');
     const isActive = session.id === project.activeSessionId;
@@ -409,8 +412,17 @@ export function render(): void {
       });
     });
 
+    if (isActive) activeTab = tab;
     tabListEl.appendChild(tab);
   }
+
+  // The rebuild above reset the scroll offset, so put it back and then pull the
+  // active tab into view — with enough tabs to overflow the strip it otherwise
+  // stays hidden, most visibly right after switching projects. 'nearest' is a
+  // no-op while the tab is already fully visible, so restoring the offset is
+  // what keeps an unrelated re-render from moving the strip at all.
+  tabListEl.scrollLeft = prevScrollLeft;
+  activeTab?.scrollIntoView({ block: 'nearest', inline: 'nearest' });
 }
 
 // Surgically update a single tab's status dot + tooltip without a full re-render.