refactor(api): restructured API for type safety, maintainability and docs generation

- These changes makes the API incombatible with previous versions
- Added new types for error handling, success responses, and health checks.
- Updated health check logic to utilize the new types for better clarity and structure.
- Refactored existing handlers to improve response consistency and error handling.
- Updated Makefile to include a new target for generating API types from Swagger.
- Updated "new agent" API to respond an encrypted cert pair

internal/net/gphttp/websocket/writer.go

@@ -0,0 +1,26 @@
+package websocket
+
+import (
+	"io"
+	"time"
+)
+
+type Writer struct {
+	msgType int
+	manager *Manager
+}
+
+func (cm *Manager) NewWriter(msgType int) io.Writer {
+	return &Writer{
+		msgType: msgType,
+		manager: cm,
+	}
+}
+
+func (w *Writer) Write(p []byte) (int, error) {
+	return len(p), w.manager.WriteData(w.msgType, p, 10*time.Second)
+}
+
+func (w *Writer) Close() error {
+	return w.manager.conn.Close()
+}