feat: close final competitive gap — professional review workflow + multi-country (MY/SG/UK)

Closes the 4th and final gap from the competitive benchmark: the
human-in-the-loop professional tier every commercial competitor pairs
with their software. Deliberately NOT a marketplace or payment
integration — a structured review-request status on each member's
Wassiyah (not_requested -> requested -> reviewed, with reviewer name
recorded), surfaced on the Mutawalli dashboard so nothing quietly ships
as final without the legally-required review being flagged.

Paired with a new whole-app jurisdiction setting since 'necessary in
certain countries' only makes sense per-jurisdiction:

- nf_families.jurisdiction (MY/SG/UK), owner-only to change — first
  UPDATE policy ever added to nf_families, which previously had none.
- New Settings-tab jurisdiction selector (JurisdictionSetting.svelte).
- Wassiyah tab and the draft will document now carry jurisdiction-
  specific legal notes: Wills Act 1959 + state Syariah (Malaysia),
  Wills Act 1838 + AMLA (Singapore), Wills Act 1837 (UK). Singapore
  added as a full third jurisdiction option, not just a stub.
- Zakat calculator's currency label and Nisab default now follow the
  family's jurisdiction (RM/SGD/GBP) instead of a hardcoded RM guess.

Covered by e2e-jurisdiction-review.cjs (13/13). Full regression:
253/253 across all suites (2 reruns confirmed as pre-existing
parallel-load flakes, not regressions).

src/App.svelte

@@ -20,6 +20,7 @@
   import FamilyTree from './lib/FamilyTree.svelte';
   import InsurancePolicies from './lib/InsurancePolicies.svelte';
   import ZakatCalculator from './lib/ZakatCalculator.svelte';
+  import JurisdictionSetting from './lib/JurisdictionSetting.svelte';
 
   let currentLang = $state('en');
   lang.subscribe(v => currentLang = v);
@@ -125,6 +126,8 @@
         </div>
         <p class="sub">Signed in as {currentSession.user.email}.</p>
 
+        <JurisdictionSetting />
+
         <div class="lang-switch">
           <span class="lang-label">Language / Bahasa</span>
           <div class="lang-buttons">