feat: update snap demo html

[stanleyyconsensys]

refactor Snap demo html to:

1. easier to add new method by adding new method into a array formWithSubmit with form id and handler

const formWithSubmit = [
      ...,
      {
        id: 'new form',
        method: methodHandler,
      },
]

2. reusable method callSnap to interacting with snap

//e.g
await callSnap(
    'starkNet_signMessage', //snap method name
    { typedDataMessage, signerAddress }, //params
);

[sonarcloud]

[consensys_starknet-snap-starknet-snap] Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
6 Code Smells

No Coverage information
0.0% Duplication

The version of Java (11.0.20) you have used to run this analysis is deprecated and we will stop accepting it soon. Please update to at least Java 17.
Read more here

[sonarcloud]

[consensys_starknet-snap-wallet-ui] Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

The version of Java (11.0.20) you have used to run this analysis is deprecated and we will stop accepting it soon. Please update to at least Java 17.
Read more here