feat: add Google Chat / Spaces as a notification provider

What problem will this feature address?

Dokploy currently offers only a set of notification channels, and there’s no native way to send deployment or application events into Google Chat / Spaces.

Teams using Google Workspace rely heavily on Chat for real-time operational visibility. Having Dokploy events appear directly inside a Chat Space improves team response times and removes context switching.

Describe the solution you'd like

Add Google Chat / Spaces as a notification provider within the Dokploy Notifications module.

In the UI, users should be able to:

• Select Google Chat as the provider
• Enter a notification name
• Paste a Google Chat incoming-webhook URL
• Select which Dokploy events should trigger notifications
• (Optional) Provide a simple message template

On event trigger, Dokploy sends an HTTP POST to the Chat webhook with a JSON payload. For an initial implementation, a basic "text" field is sufficient.

Example payload:

{
  "text": "*Deployment complete*\nApp: `my-app`\nStatus: Success\nEnvironment: Production"
}

Describe alternatives you've considered

Using an external script or automation to poll Dokploy events and forward them into Google Chat was considered, but it adds unnecessary maintenance overhead and fails to provide the clean UX of a native notification provider.

Additional context

Google Chat supports lightweight incoming webhooks with simple JSON payloads, no OAuth or bot setup required. The official formatting and webhook references are here:

• https://developers.google.com/workspace/chat/format-messages
• https://docs.cloud.google.com/workflows/docs/notify-google-chat
• https://developers.google.com/workspace/chat/quickstart/webhooks

These outline the exact payload structures and formatting capabilities needed for implementing this feature.

Will you send a PR to implement it?

No

Start in Dokploy's Notifications module and trace how existing providers, UI settings, and event triggers are connected. Verify the Google Chat provider's webhook configuration and JSON POST behavior against the linked Google Chat references; done means users can configure event notifications and receive the basic text payload in a Chat Space.