refactor(assert): consolidate browser-safe assert in browser-utils repo-wide

Addresses the re-review's two weak concerns (assert placement + incomplete
rollout). Moves the shared assert helper from libs/ui-components (a leaf UI
lib that other packages can't import without a dependency-direction
inversion) into libs/browser-utils (@tangle-network/browser-utils), the
canonical browser-safe utils package already imported across the monorepo.

Migrates the remaining 9 files off Node's `assert` built-in too —
repo-wide there are now zero `import assert from 'assert'` statements:
  apps/tangle-dapp: chainToNetwork, enumValueToNumber, useContractReadOnce
  libs/tangle-shared-ui: useWallet, useSubstrateTx, useEvmTxRelayer,
    useSubstrateStakingAssets
  libs/api-provider-environment: ConnectWallet
  libs/web3-api-provider: webb-provider

Helper signature widened to `assert(condition, message?)` to cover the
1-arg `assert(condition)` call sites Node supports. `asserts condition`
signature preserves type-narrowing at every call site.

Gates: typecheck, lint, 197 tests, build dapp+cloud all green.

Author: drewstone

apps/tangle-dapp/src/data/evm/useContractReadOnce.ts

@@ -1,5 +1,5 @@
 import ensureError from '@tangle-network/tangle-shared-ui/utils/ensureError';
-import assert from 'assert';
+import { assert } from '@tangle-network/browser-utils';
 import { useCallback } from 'react';
 import {
   Abi as ViemAbi,

apps/tangle-dapp/src/utils/chainToNetwork.ts

@@ -10,7 +10,7 @@ import {
   TANGLE_MAINNET_NETWORK,
   TANGLE_TESTNET_NATIVE_NETWORK,
 } from '@tangle-network/ui-components/constants/networks';
-import assert from 'assert';
+import { assert } from '@tangle-network/browser-utils';
 
 const chainToNetworkMap = {
   [PresetTypedChainId.TangleLocalEVM]: TANGLE_LOCAL_DEV_NETWORK,

apps/tangle-dapp/src/utils/enumValueToNumber.ts

@@ -1,4 +1,4 @@
-import assert from 'assert';
+import { assert } from '@tangle-network/browser-utils';
 
 const enumValueToNumber = <T>(enumValue: T): number => {
   assert(

libs/api-provider-environment/src/ConnectWallet/index.ts

@@ -14,7 +14,7 @@ import {
   WebbErrorCodes,
   type WalletId,
 } from '@tangle-network/dapp-types';
-import assert from 'assert';
+import { assert } from '@tangle-network/browser-utils';
 import { useObservableState } from 'observable-hooks';
 import { useCallback, useEffect, useMemo } from 'react';
 import { useWebContext } from '../webb-context/webb-context';

libs/browser-utils/src/assert.ts

@@ -0,0 +1,18 @@
+/**
+ * Browser-safe assertion. Throws a plain `Error` (not Node's `AssertionError`)
+ * so callers introduce no Node-built-in dependency and stay bundle-clean for
+ * browser targets. Carries a TypeScript `asserts condition` signature so call
+ * sites retain type-narrowing, matching the ergonomics of Node's `assert`.
+ *
+ * @param condition - The condition to check.
+ * @param message - Optional error message used when `condition` is falsy.
+ * @throws {Error} when `condition` is falsy.
+ */
+export function assert(
+  condition: unknown,
+  message?: string,
+): asserts condition {
+  if (!condition) {
+    throw new Error(message ?? 'Assertion failed');
+  }
+}

libs/browser-utils/src/index.ts

@@ -1,3 +1,4 @@
+export { assert } from './assert';
 export { default as isBrowser } from './isBrowser';
 export * from './logger';
 export * from './platform';

libs/tangle-shared-ui/src/data/staking/useSubstrateStakingAssets.ts

@@ -1,7 +1,7 @@
 import { TANGLE_TOKEN_DECIMALS } from '@tangle-network/dapp-config';
 import { isEvmAddress } from '@tangle-network/ui-components';
 import { BN } from '@polkadot/util';
-import assert from 'assert';
+import { assert } from '@tangle-network/browser-utils';
 import { useCallback, useMemo } from 'react';
 import { map } from 'rxjs';
 import { NATIVE_ASSET_ID } from '../../constants/staking';

libs/tangle-shared-ui/src/hooks/useEvmTxRelayer.ts

@@ -15,7 +15,7 @@ import {
 } from '../constants/evmPrecompiles';
 import { EvmAddress } from '@tangle-network/ui-components/types/address';
 import { assertEvmAddress } from '@tangle-network/ui-components';
-import assert from 'assert';
+import { assert } from '@tangle-network/browser-utils';
 import useViemWalletClient, {
   WalletClientTransport,
 } from './useViemWalletClient';

libs/tangle-shared-ui/src/hooks/useSubstrateTx.ts

@@ -11,7 +11,7 @@ import ensureError from '../utils/ensureError';
 import { getApiPromise } from '../utils/polkadot/api';
 import useIsMountedRef from '@tangle-network/ui-components/hooks/useIsMountedRef';
 import type { SubstrateAddress } from '@tangle-network/ui-components/types/address';
-import assert from 'assert';
+import { assert } from '@tangle-network/browser-utils';
 import { useCallback, useEffect, useState } from 'react';
 import { Hash } from 'viem';
 import useTxHistoryStore, {

libs/tangle-shared-ui/src/hooks/useWallet.ts

@@ -18,7 +18,7 @@ import ensureError from '../utils/ensureError';
 import { EIP1193Provider } from 'viem';
 import { EthereumProvider } from '@walletconnect/ethereum-provider';
 import useEvmChain from './useEvmChain';
-import assert from 'assert';
+import { assert } from '@tangle-network/browser-utils';
 
 const LAST_CONNECTED_ACCOUNT_KEY = 'lastConnectedAccountAddress';