Expose Partner client creation and service assignment navigation

app/ui/templates/components/partner_navigation_v2.html

@@ -1,6 +1,6 @@
 {% if navigation_render_location_v2|default('page') == 'global-host' or not global_role_navigation_host_v2|default(false) %}
 {#
-  UI/UX V2 Phase 1D.5 — Unified Partner navigation.
+  UI/UX V2 Phase 1D.7 — Partner client and engagement creation entry points.
   Presentation only. Existing routes and route-level permissions remain authoritative.
 #}
 {% set _partner_path = request.url.path %}
@@ -30,15 +30,21 @@
   },
   {
     'label': 'My Clients',
-    'url': '/partner/clients',
     'visible': true,
-    'active': _partner_path.startswith('/partner/clients')
+    'active': _partner_path.startswith('/partner/clients') or _partner_path.startswith('/clients'),
+    'children': [
+      {'label': 'Client Portfolio', 'url': '/partner/clients', 'active': _partner_path.startswith('/partner/clients')},
+      {'label': 'Add Client', 'url': '/clients/new', 'active': _partner_path == '/clients/new'}
+    ]
   },
   {
     'label': 'Engagements',
-    'url': '/services/engagements',
     'visible': true,
-    'active': _partner_path.startswith('/services/engagements')
+    'active': _partner_path.startswith('/services/engagements'),
+    'children': [
+      {'label': 'All Engagements', 'url': '/services/engagements', 'active': _partner_path == '/services/engagements'},
+      {'label': 'Assign Service', 'url': '/services/engagements/new', 'active': _partner_path == '/services/engagements/new'}
+    ]
   },
   {
     'label': 'Documents',