Rebrand: polkadot → pezkuwi build fixes

- Fixed TypeScript type assertion issues
- Updated imports from api-augment/substrate to api-augment/bizinikiwi
- Fixed imgConvert.mjs header and imports
- Added @ts-expect-error for runtime-converted types
- Fixed all @polkadot copyright headers to @pezkuwi

mobile/src/contexts/PolkadotContext.tsx

@@ -1,10 +1,10 @@
 import React, { createContext, useContext, useEffect, useState, ReactNode } from 'react';
-import { ApiPromise, WsProvider } from '@polkadot/api';
-import { Keyring } from '@polkadot/keyring';
-import { KeyringPair } from '@polkadot/keyring/types';
+import { ApiPromise, WsProvider } from '@pezkuwi/api';
+import { Keyring } from '@pezkuwi/keyring';
+import { KeyringPair } from '@pezkuwi/keyring/types';
 import AsyncStorage from '@react-native-async-storage/async-storage';
 import * as SecureStore from 'expo-secure-store';
-import { cryptoWaitReady } from '@polkadot/util-crypto';
+import { cryptoWaitReady } from '@pezkuwi/util-crypto';
 import { DEFAULT_ENDPOINT } from '../../../shared/blockchain/polkadot';
 
 interface Account {

mobile/src/contexts/__tests__/PolkadotContext.test.tsx

@@ -1,7 +1,7 @@
 import React from 'react';
 import { renderHook, act, waitFor } from '@testing-library/react-native';
 import { PolkadotProvider, usePolkadot } from '../PolkadotContext';
-import { ApiPromise } from '@polkadot/api';
+import { ApiPromise } from '@pezkuwi/api';
 
 // Wrapper for provider
 const wrapper = ({ children }: { children: React.ReactNode }) => (