feat(15-02): add Categories, Tags, and journal settings admin

Register the remaining YAML admin screens and the settings singleton
so a host can boot Posts, Categories, Tags, and Code journal. Posts
update and delete refuse other authors without access_other_posts.

Co-authored-by: Cursor <cursoragent@cursor.com>

admin_navigation.go

@@ -6,9 +6,7 @@ import (
 )
 
 // Navigation is the plugin's Winter registerNavigation() entry: the main
-// item journal (order 300) with its side menu. Categories and tags side
-// items are added when those controllers register (Task 2): cabana boot
-// refuses a NavigationItem.Controller that is not an AdminController.
+// item journal (order 300) with its side menu.
 func (*Plugin) Navigation() []pact.NavigationItem {
 	return []pact.NavigationItem{
 		{
@@ -33,6 +31,20 @@ func (*Plugin) Navigation() []pact.NavigationItem {
 					Permissions: []string{controllers.PermissionAccessPosts},
 					Controller:  controllers.PostsControllerID,
 				},
+				{
+					Code:        "categories",
+					Label:       "golem15.journal::lang.journal.categories",
+					Icon:        "list",
+					Permissions: []string{controllers.PermissionAccessCategories},
+					Controller:  controllers.CategoriesControllerID,
+				},
+				{
+					Code:        "tags",
+					Label:       "golem15.journal::lang.journal.tags",
+					Icon:        "tag",
+					Permissions: []string{controllers.PermissionAccessTags},
+					Controller:  controllers.TagsControllerID,
+				},
 			},
 		},
 	}