api proxy (#3603)

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## PR-Codex overview
This PR focuses on enhancing JWT utils, updating API host paths, and optimizing user authentication handling.

### Detailed summary
- Export JWT utils, fix naming of `decodeJWT`
- Update API host paths to use relative paths
- Optimize user authentication handling in various components

> The following files were skipped due to too many changes: `apps/dashboard/src/app/(dashboard)/dashboard/connect/ecosystem/[slug]/(active)/hooks/use-delete-partner.ts`, `apps/dashboard/src/components/app-layouts/app.tsx`, `apps/dashboard/src/components/buttons/TransactionButton.tsx`, `apps/dashboard/src/pages/dashboard/settings/notifications.tsx`, `apps/dashboard/src/components/engine/overview/transaction-timeline.tsx`, `apps/dashboard/src/pages/dashboard/settings/devices.tsx`, `apps/dashboard/src/app/(dashboard)/dashboard/connect/ecosystem/[slug]/(active)/hooks/use-add-partner.ts`, `apps/dashboard/src/app/(dashboard)/dashboard/connect/ecosystem/[slug]/(active)/hooks/use-update-ecosystem.ts`, `apps/dashboard/src/app/(dashboard)/dashboard/connect/pay/page.tsx`, `apps/dashboard/src/pages/dashboard/engine/index.tsx`, `apps/dashboard/src/pages/dashboard/settings/billing.tsx`, `apps/dashboard/src/components/engine/engine-instances-table.tsx`, `apps/dashboard/src/pages/dashboard/settings/usage.tsx`, `apps/dashboard/src/pages/dashboard/settings/gas-credits.tsx`, `apps/dashboard/src/pages/dashboard/settings/api-keys/index.tsx`, `apps/dashboard/src/pages/api/server-proxy/api/[...paths].tsx`, `apps/dashboard/src/pages/dashboard/connect/analytics.tsx`, `apps/dashboard/src/components/storage/your-files.tsx`, `apps/dashboard/src/pages/api/server-proxy/pay/[...paths].tsx`, `apps/dashboard/src/components/engine/engine-list.tsx`, `apps/dashboard/src/components/pay/PayAnalytics/hooks/usePayVolume.ts`, `apps/dashboard/src/components/pay/PayAnalytics/hooks/usePayNewCustomers.ts`, `apps/dashboard/src/components/pay/PayAnalytics/hooks/usePayPurchases.ts`, `apps/dashboard/src/pages/dashboard/connect/in-app-wallets.tsx`, `apps/dashboard/src/middleware.ts`, `apps/dashboard/src/components/pay/PayAnalytics/hooks/usePayCustomers.ts`, `apps/dashboard/src/pages/dashboard/connect/account-abstraction.tsx`, `apps/dashboard/src/app/login/page.tsx`, `apps/dashboard/src/app/components/ThirdwebMiniLogo.tsx`, `apps/dashboard/src/app/api/auth/ensure-login/route.ts`, `apps/dashboard/src/app/login/auth-actions.ts`, `apps/dashboard/src/components/buttons/MismatchButton.tsx`, `apps/dashboard/src/@3rdweb-sdk/react/hooks/useLoggedInUser.ts`, `apps/dashboard/src/@3rdweb-sdk/react/components/connect-wallet/index.tsx`, `apps/dashboard/src/@3rdweb-sdk/react/hooks/useApi.ts`, `apps/dashboard/src/@3rdweb-sdk/react/hooks/useEngine.ts`

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.changeset/short-pugs-impress.md

@@ -0,0 +1,5 @@
+---
+"thirdweb": patch
+---
+
+export JWT utils, fix naming of `decodeJWT`