feat(api): enhance peer session management and documentation

- Added new fields to the API for tracking connected speakers and session states across multiple nodes, including `connected_speaker_id`, `connected_speaker_label`, `session_on_speakers`, `established_on_speakers`, and `session_mismatch`.
- Implemented a new endpoint for retrieving bird protocol sessions, enhancing the agent server functionality.
- Updated the OpenAPI documentation to reflect the new fields and query parameters, improving clarity for API consumers.
- Modified the frontend to display connected speaker information and session states, providing better visibility into peer connections.
- Updated deployment documentation to clarify the configuration requirements for enabling IP forwarding on VPS.

internal/agentserver/server.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 	"time"
 
+	"evobgp/internal/birdfmt"
 	"evobgp/internal/nodecli"
 )
 
@@ -41,6 +42,7 @@ type Server struct {
 func New(cfg Config) *Server {
 	s := &Server{cfg: cfg, mux: http.NewServeMux()}
 	s.mux.HandleFunc("GET /v1/agent/health", s.handleHealth)
+	s.mux.HandleFunc("GET /v1/agent/bird/protocols", s.handleBirdProtocols)
 	s.mux.HandleFunc("POST /v1/agent/sync", s.handleSync)
 	return s
 }
@@ -68,6 +70,30 @@ func (s *Server) handleHealth(w http.ResponseWriter, r *http.Request) {
 	writeJSON(w, http.StatusOK, body)
 }
 
+func (s *Server) handleBirdProtocols(w http.ResponseWriter, r *http.Request) {
+	if !s.authorize(r) {
+		writeProblem(w, http.StatusUnauthorized, "missing or invalid Authorization")
+		return
+	}
+	sock := strings.TrimSpace(s.cfg.Socket)
+	if sock == "" {
+		writeProblem(w, http.StatusServiceUnavailable, "EVOBGP_BIRDC_SOCKET not configured")
+		return
+	}
+	ctx, cancel := context.WithTimeout(r.Context(), 10*time.Second)
+	defer cancel()
+	out, err := birdfmt.ShowProtocols(ctx, sock, strings.TrimSpace(s.cfg.BirdcBin))
+	if err != nil {
+		log.Printf("agentserver: bird protocols: %v", err)
+		writeProblem(w, http.StatusBadGateway, err.Error())
+		return
+	}
+	writeJSON(w, http.StatusOK, map[string]any{
+		"ok":       true,
+		"sessions": birdfmt.ParseBGPSessions(out),
+	})
+}
+
 func (s *Server) handleSync(w http.ResponseWriter, r *http.Request) {
 	if !s.authorize(r) {
 		writeProblem(w, http.StatusUnauthorized, "missing or invalid Authorization")