Backend improvements: views, fields_get, session, RPC stubs

- Improved auto-generated list/form/search views with priority fields,
  two-column form layout, statusbar widget, notebook for O2M fields
- Enhanced fields_get with currency_field, compute, related metadata
- Fixed session handling: handleSessionInfo/handleSessionCheck use real
  session from cookie instead of hardcoded values
- Added read_progress_bar and activity_format RPC stubs
- Improved bootstrap translations with lang_parameters
- Added "contacts" to session modules list

Server starts successfully: 14 modules, 93 models, 378 XML templates,
503 JS modules transpiled — all from local frontend/ directory.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pkg/server/stubs.go

@@ -5,16 +5,28 @@ import (
 	"net/http"
 )
 
-// handleSessionCheck returns null (session is valid if middleware passed).
+// handleSessionCheck verifies the session is valid and returns session info.
 func (s *Server) handleSessionCheck(w http.ResponseWriter, r *http.Request) {
-	s.writeJSONRPC(w, nil, nil, nil)
+	sess := GetSession(r)
+	if sess == nil {
+		if cookie, err := r.Cookie("session_id"); err == nil && cookie.Value != "" {
+			sess = s.sessions.Get(cookie.Value)
+		}
+	}
+	if sess == nil {
+		s.writeJSONRPC(w, nil, nil, &RPCError{
+			Code: 100, Message: "Session expired",
+		})
+		return
+	}
+	s.writeJSONRPC(w, nil, s.buildSessionInfo(sess), nil)
 }
 
 // handleSessionModules returns installed module names.
 func (s *Server) handleSessionModules(w http.ResponseWriter, r *http.Request) {
 	s.writeJSONRPC(w, nil, []string{
-		"base", "web", "account", "sale", "stock", "purchase",
-		"hr", "project", "crm", "fleet", "l10n_de", "product",
+		"base", "web", "contacts", "sale", "account", "stock",
+		"purchase", "crm", "hr", "project", "fleet", "product", "l10n_de",
 	}, nil)
 }
 
@@ -37,8 +49,17 @@ func (s *Server) handleManifest(w http.ResponseWriter, r *http.Request) {
 // handleBootstrapTranslations returns empty translations for initial boot.
 func (s *Server) handleBootstrapTranslations(w http.ResponseWriter, r *http.Request) {
 	s.writeJSONRPC(w, nil, map[string]interface{}{
-		"lang":       "en_US",
-		"hash":       "empty",
+		"lang": "en_US",
+		"hash": "empty",
+		"lang_parameters": map[string]interface{}{
+			"direction":    "ltr",
+			"date_format":  "%%m/%%d/%%Y",
+			"time_format":  "%%H:%%M:%%S",
+			"grouping":     "[3,0]",
+			"decimal_point": ".",
+			"thousands_sep": ",",
+			"week_start":   1,
+		},
 		"modules":    map[string]interface{}{},
 		"multi_lang": false,
 	}, nil)