fix: virtualize cloud job queue history list (#10592)

## Summary

Virtualize the shared job queue history list so opening the jobs panel
does not eagerly mount the full history on cloud.

## Changes

- **What**: Virtualize the shared queue history list used by the overlay
and sidebar, flatten date headers plus job rows into a single virtual
stream, and preserve hover/menu behavior with updated queue list tests.
- **Why `@tanstack/vue-virtual` instead of Reka virtualizers**: the
installed `reka-ui@2.5.0` does not expose a generic list virtualizer. It
only exposes `ListboxVirtualizer`, `ComboboxVirtualizer`, and
`TreeVirtualizer`, and those components inject `ListboxRoot`/`TreeRoot`
context and carry listbox or tree selection/keyboard semantics. The job
history UI is a flat grouped action list, not a selectable listbox or
navigable tree, so this uses the same TanStack virtualizer layer
directly without forcing the wrong semantics onto the component.

## Review Focus

Please verify the virtual row sizing and inter-group spacing behavior
across date headers and the last row in each group.

> [!TIP]
> Diff reads much cleaner through vscode's unified view with show
leading/trailing whitespace differences enabled

Linear: COM-304

https://tanstack.com/virtual/latest/docs/api/virtualizer

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-10592-fix-virtualize-cloud-job-queue-history-list-3306d73d3650819d956bf4b2d8b59a40)
by [Unito](https://www.unito.io)

src/components/queue/job/testUtils/mockTanstackVirtualizer.ts

@@ -0,0 +1,33 @@
+import { vi } from 'vitest'
+
+vi.mock('@tanstack/vue-virtual', async () => {
+  const { computed } = await import('vue')
+
+  return {
+    useVirtualizer: (options: {
+      count: number
+      estimateSize: (index: number) => number
+      getItemKey?: (index: number) => number | string
+    }) =>
+      computed(() => {
+        let start = 0
+        const items = Array.from({ length: options.count }, (_, index) => {
+          const size = options.estimateSize(index)
+          const item = {
+            key: options.getItemKey?.(index) ?? index,
+            index,
+            start,
+            size
+          }
+
+          start += size
+          return item
+        })
+
+        return {
+          getVirtualItems: () => items,
+          getTotalSize: () => start
+        }
+      })
+  }
+})