[client] Route agent-network through the daemon and shape env per provider

Two field-test findings drive this change: the direct-dial path needed
sudo (the profile's WireGuard key is root-owned), and a single flat
ANTHROPIC_* export set is wrong for providers that speak other API
shapes.

Relay the setup request through the daemon instead: a new
GetAgentNetworkSetup daemon RPC forwards to management over the
engine's existing peer connection, so unprivileged callers get the
caller-scoped answer the same way 'netbird status' works — no sudo,
and the key never leaves the daemon. The daemon's JSON gateway exposes
the RPC for the desktop UI for free.

Teach 'agent-network env' the per-provider environment contracts,
mirroring Claude Code's LLM-gateway configuration:
- anthropic flavor: ANTHROPIC_BASE_URL / ANTHROPIC_AUTH_TOKEN /
  ANTHROPIC_MODEL
- bedrock_api: CLAUDE_CODE_USE_BEDROCK, ANTHROPIC_BEDROCK_BASE_URL,
  CLAUDE_CODE_SKIP_BEDROCK_AUTH (the proxy injects AWS credentials)
- vertex_ai_api: CLAUDE_CODE_USE_VERTEX, ANTHROPIC_VERTEX_BASE_URL,
  CLAUDE_CODE_SKIP_VERTEX_AUTH, plus comments for the admin-supplied
  ANTHROPIC_VERTEX_PROJECT_ID and CLOUD_ML_REGION (the proxy forwards
  the URL path, so those values must be the operator's real ones)
- openai flavor: OPENAI_BASE_URL / OPENAI_API_KEY
- anything else: comment lines only — no guessed variables

Selection stays explicit: --provider picks by operator label or
catalog id and is required when several providers are authorized;
--model is validated against the provider's allowed set and required
when several models are allowed. Ambiguity renders as shell comments,
never as exports.

Linear: NET-1399

client/server/agentnetwork.go

@@ -0,0 +1,59 @@
+package server
+
+import (
+	"context"
+	"time"
+
+	"google.golang.org/grpc/codes"
+	gstatus "google.golang.org/grpc/status"
+
+	"github.com/netbirdio/netbird/client/proto"
+	mgmProto "github.com/netbirdio/netbird/shared/management/proto"
+)
+
+// GetAgentNetworkSetup relays the peer's Agent Network setup request to the
+// management server over the engine's existing connection. Running through
+// the daemon keeps the WireGuard key inside the daemon — unprivileged CLI
+// callers get a caller-scoped answer without reading the profile config.
+func (s *Server) GetAgentNetworkSetup(ctx context.Context, _ *proto.GetAgentNetworkSetupRequest) (*proto.GetAgentNetworkSetupResponse, error) {
+	s.mutex.Lock()
+	clientRunning := s.clientRunning
+	connectClient := s.connectClient
+	s.mutex.Unlock()
+
+	if !clientRunning || connectClient == nil {
+		return nil, gstatus.Errorf(codes.FailedPrecondition, "client is not running, run 'netbird up' first")
+	}
+	engine := connectClient.Engine()
+	if engine == nil {
+		return nil, gstatus.Errorf(codes.FailedPrecondition, "engine not initialized")
+	}
+
+	setupCtx, cancel := context.WithTimeout(ctx, 30*time.Second)
+	defer cancel()
+
+	setup, err := engine.GetAgentNetworkSetup(setupCtx)
+	if err != nil {
+		return nil, gstatus.Errorf(codes.Internal, "get agent network setup: %v", err)
+	}
+
+	return toDaemonAgentNetworkSetup(setup), nil
+}
+
+func toDaemonAgentNetworkSetup(setup *mgmProto.AgentNetworkSetupResponse) *proto.GetAgentNetworkSetupResponse {
+	resp := &proto.GetAgentNetworkSetupResponse{
+		Configured: setup.Configured,
+		Endpoint:   setup.Endpoint,
+		Providers:  make([]*proto.AgentNetworkProvider, 0, len(setup.Providers)),
+	}
+	for _, p := range setup.Providers {
+		resp.Providers = append(resp.Providers, &proto.AgentNetworkProvider{
+			Name:             p.Name,
+			CatalogId:        p.CatalogId,
+			ApiFlavor:        p.ApiFlavor,
+			AllModelsAllowed: p.AllModelsAllowed,
+			Models:           p.Models,
+		})
+	}
+	return resp
+}