feat(statics): add PolyxNetwork interface with v8SpecVersion and v8TxVersion

Polymesh runtime v8 is live on testnet. This commit adds the
infrastructure prerequisite fields to support the v8 migration:

- Introduce PolyxNetwork interface extending AccountNetwork with
  Polymesh-specific fields: specName, genesisHash, specVersion,
  chainName, txVersion, v8SpecVersion, and v8TxVersion.
- Update Polymesh (mainnet) and PolymeshTestnet classes to implement
  PolyxNetwork instead of plain AccountNetwork.
- Set v8SpecVersion = 8000000 and v8TxVersion = 8 on both network
  classes to reflect the Polymesh v8 runtime version.
- Add unit tests verifying v8 fields on both mainnet and testnet
  network instances.

These fields are required by BASE-2 (v8 metadata/builders) and
downstream services (indexer, wallet-platform, HSM parsing) that
need to gate logic on the runtime version.

Ticket: CECHO-1470
Session-Id: 45130683-1dd5-4330-af56-4edc9845062a
Task-Id: 64b6fe5d-9398-4f7c-9331-e87d098b8d9e

Author: nvrakesh06

modules/statics/src/networks.ts

@@ -160,6 +160,16 @@ export interface DotNetwork extends AccountNetwork {
   readonly txVersion: number;
 }
 
+export interface PolyxNetwork extends AccountNetwork {
+  readonly specName: SubstrateSpecNameType;
+  readonly genesisHash: string;
+  readonly specVersion: number;
+  readonly chainName: string;
+  readonly txVersion: number;
+  readonly v8SpecVersion: number;
+  readonly v8TxVersion: number;
+}
+
 export interface EthereumNetwork extends AccountNetwork {
   // unique chain id used for replay-protecting transactions
   readonly chainId: number;
@@ -2444,18 +2454,20 @@ class BaseChain extends Mainnet implements EthereumNetwork {
   walletImplementationAddress = '0x92db2759d1dca129a0d9d46877f361be819184c4';
 }
 
-class Polymesh extends Mainnet implements AccountNetwork {
+class Polymesh extends Mainnet implements PolyxNetwork {
   name = 'Polymesh';
   family = CoinFamily.POLYX;
   explorerUrl = 'https://polymesh.subscan.io/extrinsic/';
-  specName = 'polymesh_mainnet';
+  specName = 'polymesh_mainnet' as SubstrateSpecNameType;
   genesisHash = '0x6fbd74e5e1d0a61d52ccfe9d4adaed16dd3a7caa37c6bc4d0c2fa12e8b2f4063';
   specVersion = 7002000;
   chainName = 'Polymesh Mainnet';
   txVersion = 7;
+  v8SpecVersion = 8000000;
+  v8TxVersion = 8;
 }
 
-class PolymeshTestnet extends Testnet implements AccountNetwork {
+class PolymeshTestnet extends Testnet implements PolyxNetwork {
   name = 'PolymeshTestnet';
   family = CoinFamily.POLYX;
   explorerUrl = 'https://polymesh-testnet.subscan.io/extrinsic/';
@@ -2464,6 +2476,8 @@ class PolymeshTestnet extends Testnet implements AccountNetwork {
   specVersion = 7002000;
   chainName = 'Polymesh Testnet';
   txVersion = 7;
+  v8SpecVersion = 8000000;
+  v8TxVersion = 8;
 }
 
 class Vet extends Mainnet implements EthereumNetwork {

modules/statics/test/unit/networks.ts

@@ -1,5 +1,13 @@
 import 'should';
-import { AccountNetwork, BaseNetwork, DynamicNetwork, getNetwork, Networks, NetworkType } from '../../src/networks';
+import {
+  AccountNetwork,
+  BaseNetwork,
+  DynamicNetwork,
+  getNetwork,
+  Networks,
+  NetworkType,
+  PolyxNetwork,
+} from '../../src/networks';
 
 Object.entries(Networks).forEach(([category, networks]) => {
   Object.entries(networks).forEach(([networkName, network]) => {
@@ -131,6 +139,31 @@ describe('Cosmos-family addressPrefix', function () {
   }
 });
 
+describe('Polymesh (POLYX) v8 network fields', function () {
+  it('mainnet has v8SpecVersion and v8TxVersion', function () {
+    const network = Networks.main.polyx as unknown as PolyxNetwork;
+    network.should.have.property('v8SpecVersion', 8000000);
+    network.should.have.property('v8TxVersion', 8);
+    network.should.have.property('specVersion', 7002000);
+    network.should.have.property('txVersion', 7);
+  });
+
+  it('testnet has v8SpecVersion and v8TxVersion', function () {
+    const network = Networks.test.polyx as unknown as PolyxNetwork;
+    network.should.have.property('v8SpecVersion', 8000000);
+    network.should.have.property('v8TxVersion', 8);
+    network.should.have.property('specVersion', 7002000);
+    network.should.have.property('txVersion', 7);
+  });
+
+  it('PolyxNetwork interface has required fields', function () {
+    const network = Networks.main.polyx as unknown as PolyxNetwork;
+    network.should.have.property('specName', 'polymesh_mainnet');
+    network.should.have.property('genesisHash');
+    network.should.have.property('chainName', 'Polymesh Mainnet');
+  });
+});
+
 describe('DynamicNetwork and getNetwork', function () {
   it('DynamicNetwork should be an instance of BaseNetwork', function () {
     const network = new DynamicNetwork({ name: 'TestDynNet', type: 'testnet', family: 'eth' });