Resolve templated get_current_user_endpoint values during auth refresh fallback checks.
Added getResolvedCurrentUserEndpoint in apps/apollo/src/lib/connected_accounts/refreshAccessToken.ts.
Resolver merges backward-compatible auth config and connection data context, applies eval-field resolution, and fills mustache variables.
validateAndRefreshAccessToken now passes the resolved endpoint into refreshConnectedAccountAccessToken for OAuth2/DCR OAuth paths.
Why
Existing refresh flow was calling the current-user endpoint without template substitution, causing failures like:
NameResolutionError: Failed to resolve '{{subdomain}}.sharepoint.com'.
This fixes auth providers that require runtime fields (e.g., SharePoint, Shopify-like templates) during current-user validation after refresh failures.
Testing
Targeted implementation-only change; no full test suite run in this pass.
Behavior outside current-user endpoint template substitution is unchanged.