fix(api): add snake_case json tags to Endpoint/Task/request bodies for frontend contract

Go's encoding/json does not bridge snake_case <-> PascalCase field names,
so store.Endpoint, store.Task and the anonymous request bodies in
accounts.go/auth.go were silently decoding empty/zero values from the
frontend's snake_case JSON contract (tls_mode, role_label,
src_endpoint_id, dst_endpoint_id, src_login/pass, dst_login/pass).
Adds explicit json tags; DB layer is unaffected since pgx binds by
positional params, not struct-tag reflection.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MMHQTtnQtQqL8muAXHr9kd

internal/httpapi/accounts.go

@@ -40,7 +40,10 @@ func (s *Server) handleCreateAccount(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	var body struct {
-		SrcLogin, SrcPass, DstLogin, DstPass string
+		SrcLogin string `json:"src_login"`
+		SrcPass  string `json:"src_pass"`
+		DstLogin string `json:"dst_login"`
+		DstPass  string `json:"dst_pass"`
 	}
 	if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
 		http.Error(w, "bad json", http.StatusBadRequest)

internal/httpapi/auth.go

@@ -27,7 +27,10 @@ func NewServer(cfg config.Config, s *store.Store, orch *orchestrator.Orchestrato
 }
 
 func (s *Server) handleLogin(w http.ResponseWriter, r *http.Request) {
-	var body struct{ User, Pass string }
+	var body struct {
+		User string `json:"user"`
+		Pass string `json:"pass"`
+	}
 	if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
 		http.Error(w, "bad json", http.StatusBadRequest)
 		return

internal/store/endpoints.go

@@ -3,11 +3,11 @@ package store
 import "context"
 
 type Endpoint struct {
-	ID        int64
-	RoleLabel string
-	Host      string
-	Port      int
-	TLSMode   string
+	ID        int64  `json:"id"`
+	RoleLabel string `json:"role_label"`
+	Host      string `json:"host"`
+	Port      int    `json:"port"`
+	TLSMode   string `json:"tls_mode"`
 }
 
 func (s *Store) CreateEndpoint(ctx context.Context, e Endpoint) (int64, error) {

internal/store/json_test.go

@@ -0,0 +1,35 @@
+package store
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+)
+
+func TestEndpointJSONRoundTrip(t *testing.T) {
+	var e Endpoint
+	if err := json.Unmarshal([]byte(`{"role_label":"src","host":"h","port":993,"tls_mode":"ssl"}`), &e); err != nil {
+		t.Fatal(err)
+	}
+	if e.RoleLabel != "src" || e.Host != "h" || e.Port != 993 || e.TLSMode != "ssl" {
+		t.Fatalf("decode failed: %+v", e)
+	}
+	b, _ := json.Marshal(e)
+	if !strings.Contains(string(b), `"tls_mode":"ssl"`) || !strings.Contains(string(b), `"role_label":"src"`) {
+		t.Fatalf("marshal not snake_case: %s", b)
+	}
+}
+
+func TestTaskJSONRoundTrip(t *testing.T) {
+	var tk Task
+	if err := json.Unmarshal([]byte(`{"name":"n","src_endpoint_id":1,"dst_endpoint_id":2}`), &tk); err != nil {
+		t.Fatal(err)
+	}
+	if tk.Name != "n" || tk.SrcEndpointID != 1 || tk.DstEndpointID != 2 {
+		t.Fatalf("decode failed: %+v", tk)
+	}
+	b, _ := json.Marshal(tk)
+	if !strings.Contains(string(b), `"src_endpoint_id":1`) {
+		t.Fatalf("marshal not snake_case: %s", b)
+	}
+}

internal/store/tasks.go

@@ -3,12 +3,12 @@ package store
 import "context"
 
 type Task struct {
-	ID            int64
-	Name          string
-	SrcEndpointID int64
-	DstEndpointID int64
-	Status        string
-	FolderMapping map[string]string
+	ID            int64             `json:"id"`
+	Name          string            `json:"name"`
+	SrcEndpointID int64             `json:"src_endpoint_id"`
+	DstEndpointID int64             `json:"dst_endpoint_id"`
+	Status        string            `json:"status"`
+	FolderMapping map[string]string `json:"folder_mapping"`
 }
 
 func (s *Store) CreateTask(ctx context.Context, t Task) (int64, error) {