test(sdk-lib-mpc): load WASM before getFirstMessage on restored session

The session restore test was calling getFirstMessage() on a restored
DKG instance without first loading the WASM module. initDkg() is what
triggers loadWasmMps(); restoreSession() does not. Added initDkg()
before restoreSession() so WASM is loaded — restoreSession then
overwrites state and keys from the persisted blob as expected.

Ticket: WCI-1261
Session-Id: ac4bfdd3-68f2-464c-bb89-a871628f8093
Task-Id: bf6d94d3-a6fd-40c3-9c4a-efc7ffd08fdf

Author: BitGo Agent

modules/sdk-lib-mpc/test/unit/tss/eddsa/dkg.ts

@@ -463,7 +463,9 @@ describe('EdDSA MPS DKG', function () {
       const parsed = JSON.parse(session);
       assert.deepStrictEqual(parsed.retrofitData, retrofitUser, 'getSession must include retrofitData');
 
+      // initDkg loads the WASM module; restoreSession then overwrites state/keys from the blob
       const restored = new EddsaMPSDkg.DKG(3, 2, 0);
+      await restored.initDkg(userKP.privKey, [backupKP.pubKey, bitgoKP.pubKey]);
       restored.restoreSession(session);
 
       // Drive backup and bitgo normally so restored party can complete round 0