feat(ui): enable partial matching for collection search filters

Add "Collection name" filter using name__icontains for partial name
matching (e.g., typing "sap" matches all SAP-related collections).
Change Namespace filter from exact match to namespace__icontains
for partial namespace matching. Keywords filter is unchanged as it
uses the backend's full-text search.

Ref: AAP-67482

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: stevefulme1

src/components/collection-filter.ts

@@ -45,7 +45,8 @@ export const collectionFilter = ({
   featureFlags: { display_signatures, display_repositories },
   ignoredParams: i,
 }) => {
-  const displayNamespaces = !i.includes('namespace');
+  const displayNamespaces =
+    !i.includes('namespace') && !i.includes('namespace__icontains');
   const displayRepos = display_repositories && !i.includes('repository_name');
   const displayTags = !i.includes('tags');
 
@@ -54,13 +55,17 @@ export const collectionFilter = ({
       id: 'keywords',
       title: t`Keywords`,
     },
+    {
+      id: 'name__icontains',
+      title: t`Collection name`,
+    },
     displayRepos && {
       id: 'repository_name',
       title: t`Repository`,
       inputType: 'typeahead' as const,
     },
     displayNamespaces && {
-      id: 'namespace',
+      id: 'namespace__icontains',
       title: t`Namespace`,
     },
     displayTags && {

src/containers/search/search.tsx

@@ -152,10 +152,12 @@ class Search extends Component<RouteProps, IState> {
       collections.length === 0 &&
       !filterIsSet(params, [
         'keywords',
+        'name__icontains',
         'tags',
         'is_signed',
         'repository_name',
         'namespace',
+        'namespace__icontains',
       ]);
 
     const updateParams = (p) =>