fix(ui): pin the OPERATIONS tab bar while panel content scrolls (#31)

The TabsList is now position:sticky top:0 with a z-index above the panel
content. In wide mode it pins to the top of the OPERATIONS scroll area
(#21's center-pane scroller); in narrow mode, where the body scrolls and
there is no inner scroll container, it pins to the viewport. The existing
opaque background keeps scrolled content from showing through.

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## v0.9.8 — 2026-09-29 10:20
+- The OPERATIONS tab bar now stays pinned while its content scrolls (#31): the TabsList is `position: sticky; top: 0` with a z-index above the panel content, so it pins to the top of the OPERATIONS scroll area in wide mode (where only the center pane scrolls, #21) and to the viewport when the body scrolls in narrow mode. Its existing opaque background (`--surface-raised`) keeps scrolled content from showing through; no layout restructure needed — #21 behavior is untouched.
+- e2e: new smoke spec — shrink the viewport so WORLD MAP's fixed-height chart overflows the pane, scroll the panel to the bottom (asserting a real offset), and check the tablist's bounding box hasn't moved.
+
 ## v0.9.7 — 2026-09-29 09:59
 - LOCAL SYSTEM no longer shows the previous system after a jump (#30): WorldMapPanel owns the world state and applied the `/api/jump` response locally, so MissionControl's lifted `/api/system` state (which drives the LOCAL SYSTEM tab, CARGO HOLD and the SECTOR row) went stale until a page refresh. The panel now takes an `onJumped` callback that MissionControl wires to a `/api/system` refetch after every successful jump — same failure policy as the mount fetch (keep old state on error).
 - e2e: new smoke spec — click-to-jump on WORLD MAP, wait for the chart's turn counter to update, switch to LOCAL SYSTEM and assert its header shows the NEW current system from `/api/world` (no `page.reload()` workaround; one jump per run/retry, same pattern as the existing jump test).

components/mission-control.tsx

@@ -393,8 +393,11 @@ export function MissionControl() {
                   <TabsList
                     style={{
                       padding: '0 1rem',
-                      background: 'var(--surface-raised)',
+                      background: 'var(--surface-raised)', // opaque — content scrolls under it (#31)
                       overflowX: 'auto',
+                      position: 'sticky', // #31 — pinned in both modes: to the top of the OPERATIONS
+                      top: 0, // scroll area (wide) and to the viewport when the body scrolls (narrow)
+                      zIndex: 1,
                     }}
                   >
                     <TabsTrigger value="world-map">WORLD MAP</TabsTrigger>

e2e/smoke.spec.ts

@@ -82,6 +82,36 @@ test('active tab survives a page reload (#27)', async ({ page }) => {
   await expect(page.getByRole('tab', { name: 'CREW' })).toHaveAttribute('aria-selected', 'true');
 });
 
+test('tab bar stays pinned while panel content scrolls (#31)', async ({ page }) => {
+  await page.goto('/');
+  // Shrink the viewport so the center pane's content overflows its scroll area regardless of save state.
+  await page.setViewportSize({ width: 1280, height: 560 });
+
+  // WORLD MAP is always tall enough to overflow (fixed-height chart) — deterministic across retries.
+  await page.getByRole('tab', { name: 'WORLD MAP' }).click();
+
+  const tablist = page.getByRole('tablist');
+  await expect(tablist).toBeVisible();
+  const before = await tablist.boundingBox();
+  expect(before).not.toBeNull();
+
+  // Scroll the nearest scroll container above the tab list all the way down.
+  const scrolled = await page.evaluate(() => {
+    let el = document.querySelector('[role="tablist"]')?.parentElement ?? null;
+    while (el && !['auto', 'scroll'].includes(getComputedStyle(el).overflowY)) el = el.parentElement;
+    if (!el) throw new Error('no scroll container above the tab list');
+    el.scrollTop = el.scrollHeight;
+    return el.scrollTop;
+  });
+  expect(scrolled).toBeGreaterThan(50); // content really overflowed — guards against a vacuous pass
+
+  await expect(tablist).toBeVisible();
+  const after = await tablist.boundingBox();
+  expect(after).not.toBeNull();
+  // Pinned: the tab bar's viewport position is unchanged even though the content scrolled away (#31).
+  expect(Math.abs(after!.y - before!.y)).toBeLessThan(2);
+});
+
 test('world map shows the generated starting system and its neighbours', async ({ page }) => {
   const world = (await (await page.request.get('/api/world')).json()) as WorldState;
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "space-wanderer",
-  "version": "0.9.7",
+  "version": "0.9.8",
   "private": true,
   "scripts": {
     "dev": "next dev -p 3000",