feat(frontend): improve portfolio chart loading and i18n

[nomsoscript]

Closes #1131
Closes #1132
Closes #1130
Closes #1133

Summary

This PR resolves the first two Portfolio Chart Widget issues assigned under nomsoscript by improving the widget loading UX and adding internationalization support for labels and value formatting.

What changed

• connected the widget to the existing next-intl setup with a dedicated portfolioChartWidget namespace
• added English, Spanish, and Portuguese translations for widget labels, loading copy, and empty states
• switched currency and history date formatting to locale-aware output with useLocale() and localeToLanguageTag(...)
• added an accessible loading overlay with live status messaging
• disabled chart mode toggles and asset interactions while loading is active
• added explicit empty states for allocation, asset list, and history views
• added error rendering for failed widget loads
• added history dataset support for the trend tab
• refreshed unit coverage around i18n, loading, empty, error, and history flows

Why

These changes make the Portfolio Chart Widget feel more stable during refreshes and bring it in line with the app's existing locale system so labels and formatted values adapt to the user's language.

Notes

• this branch fully resolves the loading-state and i18n tasks
• #1130 and #1133 are still follow-up items, so they are referenced here without auto-closing them
• install, build, and tests were not run in this pass per request

[vercel]

Someone is attempting to deploy a commit to the Emmanuel's projects Team on Vercel.

A member of the Team first needs to authorize it.

[drips-wave]

@nomsoscript 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