Fix terminalUpdateStatuses to exclude failed status (#36709)

The `terminalUpdateStatuses` array included "failed", which could cause
failed operations to be incorrectly marked as succeeded if the explicit
failure check was bypassed.

## Change

Removed "failed" from `terminalUpdateStatuses` in
`memoryStoreUpdatePoller.ts`:

```typescript
// Before
const terminalUpdateStatuses: MemoryStoreUpdateStatus[] = ["completed", "superseded", "failed"];

// After
const terminalUpdateStatuses: MemoryStoreUpdateStatus[] = ["completed", "superseded"];
```

## Logic Flow

The `applyUpdateState` function handles statuses in this order:

1. **Lines 111-118**: Explicit "failed" check → sets `state.status =
"failed"`
2. **Lines 121-128**: `terminalUpdateStatuses` check → sets
`state.status = "succeeded"`
3. **Line 131**: Default → sets `state.status = "running"`

With "failed" in `terminalUpdateStatuses`, any logic error allowing
"failed" to reach line 121 would incorrectly mark it as succeeded. This
fix ensures only non-error terminal statuses ("completed", "superseded")
are treated as success.

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Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: glharper <[email protected]>

Author: Copilot

sdk/ai/ai-projects/src/api/memoryStores/memoryStoreUpdatePoller.ts

@@ -40,7 +40,7 @@ export interface CreateMemoryStoreUpdatePollerOptions {
   restoreFrom?: string;
 }
 
-const terminalUpdateStatuses: MemoryStoreUpdateStatus[] = ["completed", "superseded", "failed"];
+const terminalUpdateStatuses: MemoryStoreUpdateStatus[] = ["completed", "superseded"];
 
 function createDefaultUsage(): MemoryStoreOperationUsage {
   return {