fix: badge XLM inflation, OG hardcode, embed 404 layout, notif toggle race

[daniella-techie]

Summary

This PR addresses four related quality and correctness issues:

• [Backend] badge-awarder XLM total groups by assetCode only — custom XLM token inflates badge count #717 (implemented) — badge-awarder.ts grouped by assetCode alone, so any custom Stellar token reusing the code XLM (with a non-null issuer) inflated the native XLM total and caused incorrect total_100_xlm badge awards. Fixed by grouping by both assetCode and assetIssuer and filtering for native XLM with assetIssuer === null. Same issuer-blind pattern fixed in [Backend] Milestone progress ignores assetIssuer — multi-issuer profiles double-count #636 for milestone progress.

• [Frontend] supporters/[address] page hardcodes novasupport.xyz in Open Graph metadata #714 — supporters/[address]/page.tsx hardcodes https://novasupport.xyz in the og:url field. Preview and staging deployments emit a canonical URL pointing to production. Fix: replace with `${SITE_URL}/supporters/${params.address}` using the existing SITE_URL import from @/lib/config, matching the pattern used on all other pages.

• [Frontend] Embed page calls notFound() with no embed-specific not-found handler — renders main site layout in iframe #715 — embed/[username]/page.tsx calls notFound() with no app/embed/[username]/not-found.tsx handler. Next.js bubbles to the root 404 page which renders the full site layout inside the iframe — broken for the site owner. Fix: add a minimal not-found.tsx with a bare HTML shell and a neutral "profile no longer available" message.

• [Frontend] NotificationPreferences rapid toggle race condition reverts wrong preference #716 — notification-preferences.tsx PATCH error handler calls setPrefs((prev) => ({ ...prev, [key]: !newValue })) where newValue is captured in a stale closure. Rapid toggles of two different preferences can revert to the wrong value. Fix: replace with setPrefs((prev) => ({ ...prev, [key]: prev[key] })) to always roll back to the last-known good state, or disable all toggles while a PATCH is in-flight.

Test plan

• Send a profile 99 native XLM + 1 XLM-coded custom token → total_100_xlm badge should not be awarded
• Send a profile 100 native XLM (issuer=null) → badge is awarded
• Check og:url on a preview deployment of /supporters/[address] — should reflect preview domain, not novasupport.xyz
• Visit /embed/[username] for a deleted profile — should show the minimal embed error view, not the full site layout
• Rapidly toggle two notification preferences before either PATCH resolves — UI should not revert a preference to the wrong value

Closes #717
Closes #714
Closes #715
Closes #716

[drips-wave]

@daniella-techie Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

Learn more about application limits