Phase 2.5: UI redesign, inline quotas, toasts, Users tab

- Full UI redesign: GitHub-dark palette, custom CSS vars, better
  contrast, card layout, cleaner tables and typography
- Dashboard auto-refresh every 30s (was 60s)
- Remove Quotas tab; each share row now has a Quota button that opens
  a modal pre-filled with the share's valid users (SMB) or path (NFS)
- Replace all alert() with Bootstrap toast notifications
- Add Users tab: list system users (uid >= 1000) with SMB status,
  create user (useradd + smbpasswd), delete user, change SMB password
- Backend: /api/users GET/POST, /api/users/<name> DELETE,
  /api/users/<name>/password POST

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

PLANNING.md

@@ -64,19 +64,40 @@ on a second client). This app does not implement backup.
 
 ### Phase 2 — Dashboard & health (the main goal)
 A landing page that shows the state of the server at a glance:
-- [ ] **Daemon status** — is `smbd` running? is `nfsd` running? (green/red).
-- [ ] **Disk usage** — free / used / total for `/srv` (and per-disk if simple).
-- [ ] **All shares in one view** — every SMB share and NFS export, their paths,
+- [x] **Daemon status** — is `smbd` running? is `nfsd` running? (green/red).
+- [x] **Disk usage** — free / used / total for `/srv`.
+- [x] **All shares in one view** — every SMB share and NFS export, their paths,
       and who can access them.
-- [ ] **Per-share data used** — size on disk of each share's path (`du`).
-- [ ] **Quota usage** — for each user with a quota: used vs limit, with a
-      progress bar (e.g. "12 GB / 50 GB").
-- [ ] Auto-refresh or a manual refresh button.
+- [x] **Per-share data used** — size on disk of each share's path (`du`).
+- [x] **Quota usage** — for each user with a quota: used vs limit, with a
+      progress bar.
+- [x] Auto-refresh every 30 seconds + manual refresh button.
+
+### Phase 2.5 — UX improvements (next up)
+Improvements identified after first real test:
+
+- [x] **UI redesign** — GitHub-dark palette, better contrast, card layout,
+      breathing room. Custom CSS variables, no extra dependencies.
+- [x] **Inline quota management** — removed dedicated Quotas tab. Each SMB
+      share and NFS export row has a "Quota" button that opens a modal.
+      For SMB: lists valid_users with individual GB inputs. For NFS: manual
+      user + GB. Submits one API call per user in parallel.
+- [x] **Toast notifications** — replaced all `alert()` with Bootstrap toasts.
+- [x] **Auto-refresh every 30 s** (was 60 s).
+- [ ] **User management tab** — create, delete, and change the SMB password
+      of NAS users without touching the command line:
+      - List all system users (uid ≥ 1000), show whether they have a Samba
+        account.
+      - Create user: `useradd -M -s /usr/sbin/nologin` + `smbpasswd -a`.
+      - Delete user: `smbpasswd -x` + `userdel`.
+      - Change SMB password: `smbpasswd -s` via modal.
+      - Backend: `/api/users` GET/POST, `/api/users/<name>` DELETE,
+        `/api/users/<name>/password` POST.
 
 ### Phase 3 — Full management (complete the CRUD)
 - [ ] Working **delete** for SMB & NFS (parse config into blocks, rewrite the
       whole file — not append-only).
-- [ ] **Edit** existing shares.
+- [ ] **Edit** existing shares (path, valid users).
 - [ ] Enable/disable a share without deleting it.
 
 ### Phase 4 — Nice-to-have
@@ -84,7 +105,6 @@ A landing page that shows the state of the server at a glance:
       app drop an Apache/nginx WebDAV config snippet, same pattern as SMB/NFS,
       so it reuses the existing architecture.
 - [ ] Simple in-browser file browser for `/srv`.
-- [ ] Toast notifications instead of `alert()`.
 
 ---