feat(idlewatcher): implement real-time SSE-based loading page with enhanced UX

This major overhaul of the idlewatcher system introduces a modern, real-time loading experience with Server-Sent Events (SSE) streaming and improved error handling.

- **Real-time Event Streaming**: New SSE endpoint (`/$godoxy/wake-events`) provides live updates during container wake process
- **Enhanced Loading Page**: Modern console-style interface with timestamped events and color-coded status messages
- **Improved Static Asset Management**: Dedicated paths for CSS, JS, and favicon to avoid conflicting with upstream assets
- **Event History Buffer**: Stores wake events for reconnecting clients and debugging

- Refactored HTTP request handling with cleaner static asset routing
- Added `WakeEvent` system with structured event types (starting, waking_dep, dep_ready, container_woke, waiting_ready, ready, error)
- Implemented thread-safe event broadcasting using xsync.Map for concurrent SSE connections
- Enhanced error handling with detailed logging and user-friendly error messages
- Simplified loading page template system with better asset path management
- Fixed race conditions in dependency waking and state management

- Removed `common.go` functions (canceled, waitStarted) - moved inline for better context
- Updated Waker interface to accept context parameter in Wake() method
- New static asset paths use `/$godoxy/` prefix to avoid conflicts

- Console-style output with Fira Code font for better readability
- Color-coded event types (yellow for starting, blue for dependencies, green for success, red for errors)
- Automatic page refresh when container becomes ready
- Improved visual design with better glassmorphism effects and responsive layout
- Real-time progress feedback during dependency wake and container startup

This change transforms the static loading page into a dynamic, informative experience that keeps users informed during the wake process while maintaining backward compatibility with existing routing behavior.

internal/idlewatcher/provider/docker.go

@@ -60,11 +60,11 @@ func (p *DockerProvider) ContainerStatus(ctx context.Context) (idlewatcher.Conta
 		return idlewatcher.ContainerStatusError, err
 	}
 	switch status.State.Status {
-	case "running":
+	case container.StateRunning:
 		return idlewatcher.ContainerStatusRunning, nil
-	case "exited", "dead", "restarting":
+	case container.StateExited, container.StateDead, container.StateRestarting:
 		return idlewatcher.ContainerStatusStopped, nil
-	case "paused":
+	case container.StatePaused:
 		return idlewatcher.ContainerStatusPaused, nil
 	}
 	return idlewatcher.ContainerStatusError, idlewatcher.ErrUnexpectedContainerStatus.Subject(status.State.Status)