Fixes#20846

This PR addresses the poor user experience caused by the 30-minute hardcoded timeout on dynamic parameter WebSockets, which previously required users to refresh the page.

Key Changes:

• Backend (coderd/parameters.go):

  • Reduced the WebSocket inactivity timeout from 30 minutes to 3 minutes.
  • Implemented activity-based timeout refresh: the timer resets whenever a message is received from the client.
  • Utilizedquartz.Clock for testability of the timeout mechanism.
  • Added comprehensive tests for the new timeout and activity refresh behavior.

• Frontend (site/src/hooks/useDynamicParametersWebSocket.ts):

  • Introduced a newuseDynamicParametersWebSocket hook for managing dynamic parameter connections.
  • Integratedwebsocket-ts for automatic reconnection with exponential backoff (1-6 seconds).
  • Implemented visibility-based reconnection: the WebSocket attempts to reconnect when the browser tab becomes visible.
  • Ensures current form values are resent upon reconnection to restore server-side state.
  • Applied the new hook toCreateWorkspacePage.tsx,WorkspaceParametersPageExperimental.tsx, andTemplateEmbedPageExperimental.tsx to standardize WebSocket handling.

Why these changes?

This significantly improves the user experience by:

1. Reducing frustration: Users no longer encounter a hard disconnect after 30 minutes, especially if they briefly step away.
2. Providing seamless interaction: Auto-reconnection and state restoration make the dynamic parameter forms more robust and resilient to network interruptions or tab changes.
3. Enhancing testability: Usingquartz.Clock ensures the backend timeout logic is reliably testable.