[agent-network] Management: store, manager, synthesizer, policy engine, provider catalog, HTTP/gRPC API

Adds the account-scoped agent-network module: provider/policy/budget CRUD and
store, the reverse-proxy service synthesizer, policy selection + limit
enforcement, the provider catalog (incl. Vertex AI and AWS Bedrock entries),
and the management HTTP + proxy gRPC surfaces.

management/server/http/handlers/agentnetwork/settings_handler.go

@@ -0,0 +1,74 @@
+package agentnetwork
+
+import (
+	"encoding/json"
+	"errors"
+	"net/http"
+
+	"github.com/gorilla/mux"
+
+	"github.com/netbirdio/netbird/management/server/agentnetwork/types"
+	nbcontext "github.com/netbirdio/netbird/management/server/context"
+	"github.com/netbirdio/netbird/shared/management/http/api"
+	"github.com/netbirdio/netbird/shared/management/http/util"
+	"github.com/netbirdio/netbird/shared/management/status"
+)
+
+// addSettingsEndpoints registers the Agent Network settings routes. The
+// settings row is bootstrapped server-side on first provider create; GET reads
+// it and PUT updates the mutable collection toggles (cluster/subdomain stay
+// immutable).
+func (h *handler) addSettingsEndpoints(router *mux.Router) {
+	router.HandleFunc("/agent-network/settings", h.getSettings).Methods("GET", "OPTIONS")
+	router.HandleFunc("/agent-network/settings", h.updateSettings).Methods("PUT", "OPTIONS")
+}
+
+// updateSettings applies the collection toggles to the account's settings row.
+func (h *handler) updateSettings(w http.ResponseWriter, r *http.Request) {
+	userAuth, err := nbcontext.GetUserAuthFromContext(r.Context())
+	if err != nil {
+		util.WriteError(r.Context(), err, w)
+		return
+	}
+
+	var req api.AgentNetworkSettingsRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		util.WriteErrorResponse("couldn't parse JSON request", http.StatusBadRequest, w)
+		return
+	}
+
+	settings := &types.Settings{AccountID: userAuth.AccountId}
+	settings.FromAPIRequest(&req)
+
+	updated, err := h.manager.UpdateSettings(r.Context(), userAuth.UserId, settings)
+	if err != nil {
+		util.WriteError(r.Context(), err, w)
+		return
+	}
+	util.WriteJSONObject(r.Context(), w, updated.ToAPIResponse())
+}
+
+// getSettings returns the account's agent-network settings. The settings
+// row is bootstrapped on first provider create, so freshly-onboarded
+// accounts have nothing to read. Rather than 404-ing in that case (which
+// the dashboard would have to special-case), return a JSON null with 200
+// so consumers can branch on the body alone.
+func (h *handler) getSettings(w http.ResponseWriter, r *http.Request) {
+	userAuth, err := nbcontext.GetUserAuthFromContext(r.Context())
+	if err != nil {
+		util.WriteError(r.Context(), err, w)
+		return
+	}
+
+	settings, err := h.manager.GetSettings(r.Context(), userAuth.AccountId, userAuth.UserId)
+	if err != nil {
+		var sErr *status.Error
+		if errors.As(err, &sErr) && sErr.Type() == status.NotFound {
+			util.WriteJSONObject(r.Context(), w, nil)
+			return
+		}
+		util.WriteError(r.Context(), err, w)
+		return
+	}
+	util.WriteJSONObject(r.Context(), w, settings.ToAPIResponse())
+}