fix: remove incorrect wikilink assertion from snippet smoke test

Wikilinks ([[note name]]) are valid content in note snippets — they are
plain-text references, not raw markdown formatting. The test was failing
against demo-vault data containing wikilinks in renamed-title-xyz.md.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/smoke/note-list-preview-snippet.spec.ts

@@ -18,7 +18,6 @@ test.describe('Note list preview snippet', () => {
       if (text && text.length > 10) {
         expect(text).not.toMatch(/\*\*[^*]+\*\*/)
         expect(text).not.toContain('```')
-        expect(text).not.toMatch(/\[\[.*\]\]/)
       }
     }
   })