Fix policy automations table dropping rows for multi-host automation runs (#50684)

<!-- Add the related story/sub-task/bug number, like Resolves #123, or
remove if NA -->
**Related issue:** Resolves #50683

The policy details page's Automation runs table showed the correct run
count but rendered only one row when a single automation run covered
multiple hosts (e.g. a failing-policies webhook batch): rows are
(activity, host) pairs, so batch rows share an activity id, and the
table's default row.id keying collapsed the duplicates.

# Checklist for submitter

- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/guides/committing-changes.md#changes-files)
for more information.

## Testing

- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually

#### Before

<img width="810" height="274" alt="Screenshot 2026-08-06 at 11 36 27 AM"
src="https://github.com/user-attachments/assets/c55a54c0-5d9b-4945-b712-c2449f3a4a8c"
/>


#### After

<img width="1467" height="510" alt="Screenshot 2026-08-06 at 11 23
41 AM"
src="https://github.com/user-attachments/assets/d0e560a3-0270-49aa-989d-0812fd156813"
/>



<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Bug Fixes**
* Fixed policy automation activity tables so activities with the same ID
are displayed as separate rows for each host.
  * Corrected total run counts shown for host-specific activity rows.


<!-- end of auto-generated comment: release notes by coderabbit.ai -->

changes/50683-policy-automations-table-multi-host-rows.md

@@ -0,0 +1 @@
+- Fixed the policy automations table showing only one host for automation runs that cover multiple hosts.

frontend/pages/policies/details/components/PolicyAutomationsActivitiesTable/PolicyAutomationsActivitiesTable.tests.tsx

@@ -155,6 +155,40 @@ describe("PolicyAutomationsActivitiesTable", () => {
     expect(screen.getByPlaceholderText("Search hosts")).toBeInTheDocument();
   });
 
+  it("renders one row per host for a batch activity sharing an activity id", async () => {
+    (policiesAPI.getAutomationActivities as jest.Mock).mockResolvedValue(
+      mockResponse([
+        mockActivity({
+          id: 41,
+          type: ActivityType.RanAutomationWebhook,
+          details: { policy_id: 123 },
+          host_id: 1,
+          host_display_name: "batch-host-a",
+        }),
+        mockActivity({
+          id: 41,
+          type: ActivityType.RanAutomationWebhook,
+          details: { policy_id: 123 },
+          host_id: 2,
+          host_display_name: "batch-host-b",
+        }),
+      ])
+    );
+
+    render(
+      <PolicyAutomationsActivitiesTable
+        policy={mockPolicy}
+        currentAutomatedPolicies={[]}
+        canResetPolicy={false}
+      />
+    );
+
+    // Both (activity, host) rows must render even though they share id 41.
+    expect(await screen.findByText("batch-host-a")).toBeInTheDocument();
+    expect(screen.getByText("batch-host-b")).toBeInTheDocument();
+    expect(screen.getByText("2 runs")).toBeInTheDocument();
+  });
+
   it("shows the Reset policy button only when allowed", async () => {
     (policiesAPI.getAutomationActivities as jest.Mock).mockResolvedValue(
       mockResponse([mockActivity()], 1)

frontend/pages/policies/details/components/PolicyAutomationsActivitiesTable/PolicyAutomationsActivitiesTable.tsx

@@ -259,6 +259,13 @@ const PolicyAutomationsActivitiesTable = ({
       <TableContainer
         columnConfigs={columnConfigs}
         data={data?.activities ?? []}
+        // Each row is one (activity, host) pair, so batch automations (e.g.
+        // one webhook POST covering many hosts) return multiple rows sharing
+        // the same activity id. The default row id (row.id) would collapse
+        // them into a single rendered row.
+        getRowId={(row: IPolicyAutomationActivity) =>
+          `${row.id}-${row.host_id}`
+        }
         isLoading={isLoading}
         manualSortBy
         pageIndex={page}