Fix navbar: SVG logos, Settings menu, Logout handler

- Image handler now returns SVG placeholders for company logo and user
  avatars instead of broken 1x1 PNG (fixes yellow border in navbar)
- Supports both query-param (?model=&field=) and path-style URLs
  (/web/image/res.partner/2/avatar_128)
- Added Settings app menu with Users & Technical sub-menus
- Added actions for Settings (company form), Users list, Sequences
- Added /web/session/logout handler that clears session + cookie
- Added logout to middleware whitelist

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

pkg/server/menus.go

@@ -16,7 +16,7 @@ func (s *Server) handleLoadMenus(w http.ResponseWriter, r *http.Request) {
 		"root": map[string]interface{}{
 			"id":                  "root",
 			"name":                "root",
-			"children":            []int{1, 2, 3, 4, 5, 6, 7, 8, 9},
+			"children":            []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 100},
 			"appID":               false,
 			"xmlid":               "",
 			"actionID":            false,
@@ -330,6 +330,49 @@ func (s *Server) handleLoadMenus(w http.ResponseWriter, r *http.Request) {
 			"webIconDataMimetype": nil,
 			"backgroundImage":     nil,
 		},
+		// Settings
+		"100": map[string]interface{}{
+			"id":                  100,
+			"name":                "Settings",
+			"children":            []int{101, 102},
+			"appID":               100,
+			"xmlid":               "base.menu_administration",
+			"actionID":            100,
+			"actionModel":         "ir.actions.act_window",
+			"actionPath":          false,
+			"webIcon":             "fa-cog,#71639e,#FFFFFF",
+			"webIconData":         nil,
+			"webIconDataMimetype": nil,
+			"backgroundImage":     nil,
+		},
+		"101": map[string]interface{}{
+			"id":                  101,
+			"name":                "Users & Companies",
+			"children":            []int{},
+			"appID":               100,
+			"xmlid":               "base.menu_users",
+			"actionID":            101,
+			"actionModel":         "ir.actions.act_window",
+			"actionPath":          false,
+			"webIcon":             nil,
+			"webIconData":         nil,
+			"webIconDataMimetype": nil,
+			"backgroundImage":     nil,
+		},
+		"102": map[string]interface{}{
+			"id":                  102,
+			"name":                "Technical",
+			"children":            []int{},
+			"appID":               100,
+			"xmlid":               "base.menu_custom",
+			"actionID":            102,
+			"actionModel":         "ir.actions.act_window",
+			"actionPath":          false,
+			"webIcon":             nil,
+			"webIconData":         nil,
+			"webIconDataMimetype": nil,
+			"backgroundImage":     nil,
+		},
 	}
 
 	json.NewEncoder(w).Encode(menus)