fix: HTML attribute quoting in hx-confirm, test assertion precision (A11-T1)

Critical quoting fix: the hx-confirm attribute now uses U+201D (") for the
closing German quote instead of ASCII " (0x22), which was terminating the
attribute early and losing the confirm message text. The template now
correctly contains: hx-confirm="Szenario „{{ sc.name }}" mit allen..."

Test enhancement: restored the complete assertion text from the brief and
added HTML parsing verification to ensure the attribute value matches exactly
with correct typographic quotes.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

finance/app/templates/szenarien.html

@@ -14,7 +14,7 @@
       · Einmalposten: {{ 'ja' if sc.include_planned else 'nein' }}
       <button type="button" onclick="toggleEdit('sc', {{ sc.id }}, true)">Bearbeiten</button>
       <button type="button" hx-delete="/api/scenarios/{{ sc.id }}" hx-swap="none"
-              hx-confirm="Szenario „{{ sc.name }}" mit allen Einträgen wirklich löschen?"
+              hx-confirm="Szenario „{{ sc.name }}” mit allen Einträgen wirklich löschen?"
               hx-on::after-request="if(event.detail.successful){window.location.reload()}">Löschen</button>
     </p>
     <div id="sc-edit-{{ sc.id }}" hidden>