fix: fix token import flow (#4924)

## Explanation

As autodetection is now multi-chain, the `addTokens` function must be
adjusted by taking the `allTokens` and filter on `chainId` into account
to avoid importing the wrong tokens.

The `addTokens` function currently operates by taking the existing list
of imported tokens ( without considering the network ) and adding the
tokens specified in the `tokensToImport` parameter. This approach can
result in incorrect tokens being imported, as it doesn’t filter by
chain. To address this, we use `allTokens` to ensure accurate filtering
by chain.

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## References

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### `@metamask/assets-controllers`

- **CHANGED**: addTokens should rely now on `allTokens`


## Checklist

- [ ] I've updated the test suite for new or updated code as appropriate
- [ ] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [ ] I've highlighted breaking changes using the "BREAKING" category
above as appropriate
- [ ] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes

packages/assets-controllers/src/TokensController.ts

@@ -462,16 +462,16 @@ export class TokensController extends BaseController<
    */
   async addTokens(tokensToImport: Token[], networkClientId?: NetworkClientId) {
     const releaseLock = await this.#mutex.acquire();
-    const { ignoredTokens, allDetectedTokens } = this.state;
+    const { allTokens, ignoredTokens, allDetectedTokens } = this.state;
     const importedTokensMap: { [key: string]: true } = {};
     // Used later to dedupe imported tokens
-    const newTokensMap = Object.values(tokensToImport).reduce(
-      (output, token) => {
-        output[token.address] = token;
-        return output;
-      },
-      {} as { [address: string]: Token },
-    );
+    const newTokensMap = [
+      ...(allTokens[this.#chainId]?.[this.#getSelectedAccount().address] || []),
+      ...tokensToImport,
+    ].reduce((output, token) => {
+      output[token.address] = token;
+      return output;
+    }, {} as { [address: string]: Token });
     try {
       tokensToImport.forEach((tokenToAdd) => {
         const { address, symbol, decimals, image, aggregators, name } =