… to fix stale cache on slow connections cp-7.67.0 (#26324)

## **Description**

Fixes [TAT-2597](https://consensys-mesh.atlassian.net/browse/TAT-2597)
and [TAT-2598](https://consensys-mesh.atlassian.net/browse/TAT-2598):
After the preload PR merged, slow connections caused StreamChannels to
exhaust 150 polling retries (30s) in `ensureReady()` and silently give
up, leaving users with stale REST cache and no live WebSocket data —
positions not appearing after trade, missing prices.

**Root Cause:** `StreamChannel.ensureReady()` used blind polling
(`isReady` every 200ms × 150 retries) with no awareness of WebSocket
connection state. On slow connections, the connection had not even
established yet, so polling burned through all retries before data could
arrive.

**Fix:**
- `PerpsConnectionManager.waitForConnection()` — exposes init/reconnect
promises so channels can `await` instead of blind-polling
- `StreamChannel.ensureReady()` — detects `isConnecting` state and
awaits the connection promise via `awaitConnectionThenConnect()`

**Result:** PriceStreamChannel retries dropped from **33 → 0** on device
after this fix.

## **Changelog**

CHANGELOG entry: Fixed stale cache on slow connections where positions
and prices were not updating after a trade

## **Related issues**

Fixes: [TAT-2597](https://consensys-mesh.atlassian.net/browse/TAT-2597),
[TAT-2598](https://consensys-mesh.atlassian.net/browse/TAT-2598)

## **Manual testing steps**

```gherkin
Feature: Perps live data on slow connections

  Scenario: user opens a trade on a slow connection
    Given the app is connected to a slow 3G network
    And the user has navigated to the Perps trading screen

    When user opens a new position
    Then the position appears immediately in the positions list
    And price stream connects without excessive retries

  Scenario: user recovers from network drop
    Given the user is viewing live perps positions
    And the network connection drops momentarily

    When the network connection is restored
    Then live WebSocket data resumes without stale cache
```

## **Screenshots/Recordings**

### **Before**

<!-- PriceStreamChannel: 33 retries before data appears, positions
missing on slow connections -->

### **After**

<!-- PriceStreamChannel: 0 retries, positions appear immediately -->

## **Pre-merge author checklist**

- [x] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask Mobile
Coding
Standards](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
- [x] I've included tests if applicable
- [x] I've documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [ ] I've applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [ ] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [ ] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.

[TAT-2597]:
https://consensyssoftware.atlassian.net/browse/TAT-2597?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ
[TAT-2598]:
https://consensyssoftware.atlassian.net/browse/TAT-2598?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ
[TAT-2597]:
https://consensyssoftware.atlassian.net/browse/TAT-2597?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Medium Risk**
> Touches Perps connection/stream reconnection timing and retry logic;
mistakes could cause missed subscriptions or delayed real-time updates,
though changes are localized and well-covered by tests.
> 
> **Overview**
> Prevents Perps stream channels from burning through retry polling on
slow connections by making `StreamChannel.ensureReady()` detect
`isConnecting` and wait on the connection manager before retrying
`connect()`.
> 
> Adds `PerpsConnectionManager.waitForConnection()` (awaits
init/reconnect promises, swallowing rejections) and introduces
`awaitConnectionThenConnect()` with a sentinel timer to avoid duplicate
awaits, plus a small `deferConnect()` timer cleanup fix and a shared
`PERPS_CONSTANTS.ConnectRetryDelayMs` constant.
> 
> Expands unit tests to cover the new await/guard behavior
(duplicate-await prevention, resolve/reject fallbacks) and updates
market-data channel tests to use the new retry delay constant.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
7e0d599. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->