* feat(gateway): add GET /api/features for frontend feature gating (#3757)
* feat(agents): add useAgentsApiEnabled feature-flag hook (#3757)
* feat(agents): gate /workspace/agents segment on agents_api flag (#3757)
* feat(sidebar): grey out Agents button with tooltip when agents_api disabled (#3757)
* fix(sidebar): show disabled Agents tooltip on hover, harden a11y + e2e (#3757)
- Wrap the disabled Agents button in a hoverable tooltip trigger so the
'feature not enabled' hint shows in the expanded sidebar, not only when
collapsed (the SidebarMenuButton tooltip prop is hidden unless collapsed).
- Add tabIndex={-1} and drop the redundant onClick preventDefault.
- Add e2e coverage for the disabled state + a default /api/features mock.
* style(sidebar): move cursor-not-allowed to the hoverable span (#3757)
* test(agents): anchor e2e agents-API request filter with a path regex (#3757)
* fix(agents): don't expose backend config in disabled message; tell user to contact admin (#3757)
The disabled panel previously said 'Set agents_api.enabled: true in
config.yaml', leaking backend configuration to end users. Replace with a
generic 'not enabled on this server, contact your administrator' message
(matching the existing nameStepApiDisabledError copy). e2e now asserts the
contact-admin message and that no config.yaml/agents_api text is rendered.
* make format
* fix(agents): keep agents_api flag sticky during /api/features outage (#3757)
Failing open re-mounted the agents UI and re-triggered the 403 storm when
agents_api was genuinely disabled and /api/features was down. Persist the
last definitive answer and fall back to it (sticky) before failing open,
only failing open when nothing has ever been observed. Read the cached
value after mount so the first client render matches the server (no
hydration mismatch on the non-loading-gated sidebar).
* fix(sidebar): make disabled Agents entry keyboard/SR accessible (#3757)
The disabled-state explanation was hover-only: tabIndex={-1} removed the
entry from the tab order and the reason lived only in a pointer-triggered
tooltip. Keep it in the tab order and wire aria-describedby to a
visually-hidden reason so keyboard and screen-reader users learn why it is
disabled.
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Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
