Put Archify right-click entries in their own section at the bottom

Explorer and editor-tab context menus: the Archify commands used the
built-in navigation group and were mixed with New File, New Folder and
the rest. They now use a z_archify group, which VS Code sorts last and
separates with a divider.

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## Unreleased
+
+- **Right-click menus:** Archify commands (New Diagram Archify…, Open Preview, Render to HTML File…, Open in Archify HTML Viewer) now sit in their own section at the bottom of the Explorer and editor-tab menus, instead of between New File, New Folder and the other built-in entries.
+
 ## 0.5.1 — 2026-10-07
 
 - **Clearer descriptions:** the Marketplace description, README and messages now say plainly that diagrams are `.archify` files in YAML. Archify's own JSON files (`*.architecture.json`, …) and rendered HTML are described as also supported, in their own section.

package.json

@@ -154,29 +154,29 @@
         {
           "command": "archify.newDiagram",
           "when": "explorerResourceIsFolder",
-          "group": "navigation@10"
+          "group": "z_archify@1"
         },
         {
           "command": "archify.showPreview",
           "when": "resourceFilename =~ /(\\.archify|\\.(architecture|workflow|sequence|dataflow|lifecycle)\\.json)$/",
-          "group": "navigation@20"
+          "group": "z_archify@2"
         },
         {
           "command": "archify.renderToHtml",
           "when": "resourceFilename =~ /(\\.archify|\\.(architecture|workflow|sequence|dataflow|lifecycle)\\.json)$/",
-          "group": "navigation@21"
+          "group": "z_archify@3"
         },
         {
           "command": "archify.openHtmlViewer",
           "when": "resourceExtname == .html",
-          "group": "navigation@20"
+          "group": "z_archify@2"
         }
       ],
       "editor/title/context": [
         {
           "command": "archify.showPreview",
           "when": "resourceFilename =~ /(\\.archify|\\.(architecture|workflow|sequence|dataflow|lifecycle)\\.json)$/",
-          "group": "1_open"
+          "group": "z_archify@1"
         }
       ],
       "file/newFile": [