QA Promotion: Async Bulk Mail Share/Export, Upload Center Activation, and Reliability Fixes

A batch promotion of recent frontend work into the QA environment, bundling 7 feature and fix PRs across the Admin and Mail apps. Highlights include background (async) processing for large mail share and export operations, the ability to activate/deactivate upload centers from the admin grid, clearer partial-failure reporting on bulk operations, and several stability fixes for pagination, file previews, and document tags.

Large mail share and export actions previously assumed a synchronous response, which does not scale to high-volume selections. Admins also had no in-grid way to enable or disable an upload center, the email-reminders list paged incorrectly against the backend's contract, document-tag lookups built fragile hand-rolled URLs, and Filestack preview links could break once their signed credentials expired. This promotion moves those fixes from dev into QA for validation.

• Mail users: Bulk share and bulk export of large selections now run as background jobs with live progress, instead of blocking or timing out.
• Bulk operations: When some items in a batch fail, users see normalized, readable per-item failure reasons rather than raw error blobs.
• Admins: Can activate or deactivate an upload center directly from the row menu; a deactivated center stays visible in the grid instead of vanishing.
• Stability: Email-reminder pages now load correct results, document-tag filtering hits the right URL, and document previews refresh their credentials before expiry.

Frontend-only (apps/admin, apps/mail, packages/types); 49 files. Notable PRs included:

• #1022 Async mail bulk export/share: ServerExportModal and share dialogs now detect HTTP 202 + JSON job references and route them into the bulk-progress UI; ShareWithinSystemDialog split into view/helpers/types/hooks (recipient cards, normalizers).
• #1024 Partial bulk-failure details: BulkOperationProgress decomposed into BulkOperationProgressPanel + useBulkOperationProgressState hook + types; added failure-message normalization and a SHARE_STATUS_CONFIG.
• #1025 Upload center status toggle: new useActivate/DeactivateUploadCenter mutations (via the update endpoint's is_active), permission-gated on update_upload_center, with optimistic cache patching so toggled rows persist.
• #1023 Email reminders pagination: switched from skip offset to 1-based page and totalPages.
• #1007 Filestack credential refresh: hasUsableFilestackCredentials guard + expiry-based refresh; credentials fetched lazily only when files are present.
• #1027 Document tags URL: replaced a manual query-string builder with the shared http.get(route, params) helper.
• #1029: hides the standalone Documents page status-update action (showStatusUpdateActions={false}).
• Refreshed generated API types and added a docs-only grid freshness/load-strategy guide (355 lines).

Moderate. The async export/share path and the large BulkOperationProgress/ShareWithinSystemDialog refactors (hundreds of lines moved) touch high-traffic flows and depend on the backend returning 202 with the expected job_id shape; a contract mismatch would break share/export. The optimistic upload-center cache update could briefly show stale status if a toggle request fails. Mitigation: changes are isolated to the frontend, status toggles roll back the cache and toast on error, and this promotion targets QA specifically so these paths are validated before reaching Production.

• Bulk share/export: Trigger a large select-all share and a large export; confirm the progress panel appears, tracks to completion, and shows per-item failures when some items fail.
• Upload centers: Activate and deactivate a center from the row menu; confirm the row stays visible, status updates, and the action is hidden for users lacking update_upload_center.
• Email reminders: Page forward/back and verify correct rows and accurate total page count.
• Document tags: Filter documents by tag/document type and confirm results load (correct request URL).
• Previews: Open a Filestack-backed preview; confirm it stays valid and refreshes near credential expiry.
• Documents page: Confirm the standalone Documents grid no longer exposes the status-update bulk action.