VS Code telemetry needs to be more granular

[maisarissi]

The telemetry is mostly put in when registering the commands.
Today, the ms-graph.kiota/kiota.openApiExplorer.generateClient command encompasses all the generation events (client, manifest, plugin).
Having a more granular telemetry for each generation event would helps us understand better the extension use.
So we need to have separate events for:

• client
• api plugin (copilot plugin)
• api manifest
• openai plugin (other)

[petrhollayms]

@thewahome Could you please check whether we could also add an attribute about the mode ("ttk", empty or other future value)?