feat: new bridge asset picker and token list endpoints (#37685)

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## **Description**

Refactors bridge asset selection to use assetId instead of address,
simplifies state management, and introduces a new asset picker component
with improved token fetching

### Data/State changes
- Replace address references with assetId (simplifies slippage defaults
and asset deduplication)
- Read network allowlist from chainRanking LD config
- Combine setFromChain and setFromToken actions; asset picker manages
local selectedNetwork state, so network only changes when setFromToken
changes
- Refactor useMultichainBalances into selectors for type safety and to
simplify balance and metadata lookups

### Components
- Replace AssetPicker with a new implementation using the search and
popular getToken endpoints for token lists

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## **Changelog**

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CHANGELOG entry: feat: implement new bridge asset picker and read token
data from new popular and search api endpoints

## **Related issues**

Fixes:

## **Manual testing steps**

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## **Screenshots/Recordings**

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### **Before**

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### **After**

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## **Pre-merge author checklist**

- [ ] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [ ] I've completed the PR template to the best of my ability
- [ ] I’ve included tests if applicable
- [ ] 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-extension/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.



<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Modernizes bridge asset discovery and state.
> 
> - Introduces new bridge asset picker using `getTokens/popular` and
`getTokens/search`; consolidates `setFromChain` into `setFromToken` and
updates network switching logic
> - Migrates bridge to CAIP `assetId`/`chainId` throughout (balances,
prices, token pairs, images); adds `BRIDGE_ONLY_CHAINS`, CAIP explorer
URL map, and network image mapping
> - Updates Security Alerts API utilities to accept CAIP ids and convert
to service chain names
> - Broad test refresh: new selector unit tests, extensive e2e updates
(ETH/L2, Tron, Solana, Bitcoin), new fixtures/mocks/seed data; adjusts
expectations for quotes/metrics
> - i18n cleanup: remove unverified-token strings; add
`bridgeTokenNotFound`; minor copy fixes
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
5508ef7. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

---------

Co-authored-by: hunty <[email protected]>
Co-authored-by: MetaMask Bot <[email protected]>

Author: 3 people