Manage Members page: no breadcrumb or back link to parent org/group

## Bug The **Manage Members** page (for both organizations and groups) has no breadcrumb trail and no back link. Users land on the page with no obvious way to return to the parent organization or group they came from. See screenshot: the page starts directly with the `Manage Members` title and the tab strip (All Members / Owners / Hosts / Members / Pending Requests / Blocked). No `← Back to Organization` or `Organizations › Eco Studio Stockholm › Manage Members` context. ## Expected One of the following, consistent with other detail pages on the site: - **Breadcrumb** above the title: `Organizations › {Org name} › Manage Members` (and equivalent for groups: `Organizations › {Org} › Groups › {Group} › Manage Members`). - **Back link** next to / above the title: `← Back to {Org name}` — matches the pattern already used on the group public page. Ideally both: breadcrumb for hierarchy, back link for the primary return path. ## Affected routes - `/organizations/{slug}/members` — org Manage Members - `/organizations/{slug}/groups/{slug}/members` — group Manage Members (if separate) Please verify both variants; add breadcrumbs/back link to each. ## Reproduction 1. Open any organization you own/manage. 2. Click **Manage Members** from the org settings / dashboard menu. 3. Observe: no breadcrumb, no back link, only the browser back button returns the user. ## Related Similar navigation gaps have been filed before — e.g. the event-detail back-nav bug (Fider #60) and the "Back to Rings" mis-label (Fider #59). Worth auditing the other manage/settings pages (Org Settings, Group Settings) in the same MR for consistent breadcrumb coverage. ## Found by Manual testing