fix: restore devnet/testnet e2e contract tests

[nelitow]

Summary

Fix devnet/testnet E2E contract tests that were completely broken due to a Babel transpilation error, and resolve several secondary issues causing test flakiness.

Root cause: The fuels SDK code generator produces TypeScript declare class fields in CustomAsset.ts, which are incompatible with Playwright's Babel transform pipeline. This caused a SyntaxError that prevented all devnet/testnet E2E tests from running.

Additional fixes:

• Replace brittle XPath account selector with DB lookup in getAddressForAccountNumber — accounts are sorted alphabetically in the UI, not by creation order
• Fix getWalletPopupPage race condition where popups opening before waitForEvent was registered were missed — now uses concurrent polling + event listening
• Fix chain ID detection in dApp Providers.tsx to correctly distinguish devnet vs testnet based on provider URL
• Wait for network switch confirmation in addNetwork to prevent downstream flakiness
• Update devnet network name to match actual chain name (Fuel Ignition Sepolia Devnet)
• Fix popup URL predicate in FuelWalletTestHelper to include .html extension
• Redeploy MainContract and ExternalContract to both devnet and testnet with fresh state (old contracts had accumulated state causing ArithmeticOverflow)
• Update fast-xml-parser override to resolve critical audit vulnerability

Checklist

• I've added error handling for all actions/requests, and verified how this error will show on UI. (or there was no error handling)
• I've reviewed all the copy changed/added in this PR, using AI if needed. (or there was no copy changes)
• I checked the resulting UI both in Light and Dark mode (or no UI changes were made)
• I reviewed the entire PR myself (preferably, on GH UI)

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PR Summary

Medium Risk
Touches Playwright test helpers used across suites and updates generated contract bindings/contract IDs, which can affect test stability and environment targeting even though runtime wallet logic is largely unchanged.

Overview
Restores reliability of devnet/testnet E2E contract tests by hardening Playwright wallet automation and aligning test configuration with current networks and deployments.

This removes brittle UI-driven account address retrieval (XPath + clipboard) in favor of querying the wallet DB and normalizing via Address, fixes a race in getWalletPopupPage by combining page-event listening with polling, and adds a wait after network switching. Contract-test setup is updated to infer chainId from VITE_FUEL_PROVIDER_URL, refreshes deployed contract IDs, and regenerates contract bindings (dropping problematic declare blocks) to avoid Playwright/Babel syntax errors; a small timing tweak reduces unnecessary waits. Also updates dependency overrides/lockfile for fast-xml-parser and adds a changeset for patch releases.

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