…aused by token warning in unified swaps context cp-7.73.0 (#28361)

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## **Description**

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When a destination token has a security warning (e.g. a Blockaid
malicious/suspicious flag), the unified swaps bridge view was entering
an infinite quote request loop.

**Root cause:** `tokenWarning` was included as a dependency of the
`useMemo` that builds the analytics `context` object in
`useUnifiedSwapBridgeContext`. `tokenWarning` is itself derived from
quote results (blockaid data returned by the bridge controller). This
created a feedback cycle:

```
Quote fetched → tokenWarning updates → context object recreates
→ updateQuoteParams identity changes → useEffect fires
→ new quote request → repeat ∞
```

**Fix:** Remove `tokenWarning` from the `useMemo` dependency array and
clear `security_warnings` to `[]` for now. The `security_warnings` field
will be populated properly in the bridge controller instead, removing
the React dependency cycle entirely.

## **Changelog**

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CHANGELOG entry: Fixed a bug that caused repeated quote requests when
swapping to a token with a security warning.

## **Related issues**

Fixes:

## **Manual testing steps**

```gherkin
Feature: Unified Swaps/Bridge quote fetching with token warnings

  Scenario: user swaps to a token with a Blockaid security warning
    Given the user has opened the Swap/Bridge screen
    And the user has selected a source token with sufficient balance

    When the user selects a destination token that has a Blockaid security warning
    And the user enters a valid source amount
    Then the app fetches a quote once
    And does not repeatedly fire additional quote requests
    And the security warning banner is displayed on screen

  Scenario: user swaps to a normal token (no warning)
    Given the user has opened the Swap/Bridge screen
    And the user has selected a source token with sufficient balance

    When the user selects a destination token with no security warning
    And the user enters a valid source amount
    Then the app fetches a quote once
    And quote results are displayed normally
```

## **Screenshots/Recordings**

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before and after of your change. -->

### **Before**

N/A

### **After**


Uploading Screen Recording 2026-04-02 at 4.24.51 PM.mov…



## **Pre-merge author checklist**

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- [x] I've completed the PR template to the best of my ability
- [x] I've included tests if applicable
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## **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.

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<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Low Risk**
> Low risk: small change limited to analytics context memoization, but
it temporarily drops `security_warnings` data which could affect
warning-related telemetry until re-populated elsewhere.
> 
> **Overview**
> Prevents an infinite bridge quote re-fetch loop by removing
destination token warning state from `useUnifiedSwapBridgeContext`’s
memoized context object.
> 
> `security_warnings` is now always an empty array (*TODO*) and the
`useMemo` dependency list no longer includes the warning selector,
stabilizing the `context` identity passed into
`BridgeController.updateBridgeQuoteRequestParams`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
21dec81. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->