fix(search): preserve empty-query discovery results

web/e2e/search-page-full.spec.ts

@@ -41,7 +41,19 @@ test.describe('Search Input (Real API)', () => {
 
   // TC_SEARCH_INPUT_003 P0 - empty search shows the default discovery list
   test('TC_SEARCH_INPUT_003: empty search shows the default discovery list', async ({ page }) => {
+    const emptyQueryResponse = page.waitForResponse((response) => {
+      if (!response.url().includes('/api/web/skills?')) {
+        return false
+      }
+
+      const url = new URL(response.url())
+      return response.status() === 200
+        && url.searchParams.has('q')
+        && url.searchParams.get('q') === ''
+    })
+
     await page.goto(searchUrl(''))
+    await emptyQueryResponse
     await expect(page).toHaveURL(/\/search/)
     await expect(getSearchCards(page).first()).toBeVisible({ timeout: 10_000 })
   })

web/src/shared/hooks/skill-query-helpers.test.ts

@@ -16,6 +16,18 @@ describe('buildSkillSearchUrl', () => {
   it('returns the base skills endpoint when no search params are provided', () => {
     expect(buildSkillSearchUrl({})).toBe('/api/web/skills')
   })
+
+  it('keeps an empty q parameter when the search query is an empty string', () => {
+    expect(buildSkillSearchUrl({ q: '' })).toBe('/api/web/skills?q=')
+  })
+
+  it('normalizes whitespace-only queries to an empty q parameter', () => {
+    expect(buildSkillSearchUrl({
+      q: '   ',
+      sort: 'relevance',
+      page: 0,
+    })).toBe('/api/web/skills?q=&sort=relevance&page=0')
+  })
 })
 
 describe('shouldEnableNamespaceMemberCandidates', () => {

web/src/shared/hooks/skill-query-helpers.ts

@@ -6,7 +6,7 @@ export function buildSkillSearchUrl(params: SearchParams) {
   const queryParams = new URLSearchParams()
   const normalizedQuery = normalizeSearchQuery(params.q ?? '')
 
-  if (normalizedQuery) {
+  if (params.q !== undefined) {
     queryParams.append('q', normalizedQuery)
   }