feat!: separate local events and server events

[santhoshvai]

CLA

• [x] I have signed the Stream CLA (required).
• [x] Code changes are tested

Description of the changes, What, Why, and How?

When supplying event callbacks, this PR helps with stricter typing.

For example,

client.on('connection.changed', (event) => console.log(event.online));
// only `online` will be shown by the IDE for code-completion

Breaking change

Clients of the SDK cannot use the fields directly in if statements, For example,

function func(event: Event<StreamChatGenerics>) {
  // this would error out, as TS would complain that event doesn't have online field
  if (event.online) {
    console.log(event.online);
  }
  // the correct way
  if (event.type === 'connection.changed') {
    console.log(event.online)
  }
}

[github-actions[bot]]

Size Change: +1.31 kB (0%)

Total Size: 309 kB

Filename	Size	Change
dist/browser.es.js	67.5 kB	+248 B (0%)
dist/browser.full-bundle.min.js	36.9 kB	+122 B (0%)
dist/browser.js	68.5 kB	+445 B (+1%)
dist/index.es.js	67.6 kB	+250 B (0%)
dist/index.js	68.3 kB	+249 B (0%)

_{compressed-size-action}

[vishalnarkhede]

We will pick this up later!