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+# Design: Session Archive, Sunday Badge, Multi-Select, and Pagination
+
+## Overview
+
+Four enhancements to the History page and Session Detail page:
+
+1. **Archive/Unarchive sessions** — hide sessions from the default history list, with a filter to view archived sessions
+2. **Sunday "Game Night" badge** — visual indicator on session cards when a session took place on a Sunday
+3. **Multi-select mode** — bulk archive and delete operations on the History page (admin only)
+4. **Pagination options** — configurable number of sessions shown (5, 10, 25, 50, All)
+
+## Backend
+
+### Schema Change
+
+Add `archived INTEGER DEFAULT 0` to the `sessions` table using the existing defensive `ALTER TABLE` pattern in `database.js`:
+
+```js
+try {
+  db.exec(`ALTER TABLE sessions ADD COLUMN archived INTEGER DEFAULT 0`);
+} catch (err) {
+  // Column already exists
+}
+```
+
+No new tables. No migration file.
+
+### New Endpoints
+
+#### `POST /api/sessions/:id/archive`
+
+- **Auth:** Required
+- **Action:** Sets `archived = 1` on the session
+- **Constraints:** Returns 400 if the session is still active (`is_active = 1`). Returns 404 if session not found.
+- **Response:** `{ success: true }`
+
+#### `POST /api/sessions/:id/unarchive`
+
+- **Auth:** Required
+- **Action:** Sets `archived = 0` on the session
+- **Constraints:** Returns 404 if session not found.
+- **Response:** `{ success: true }`
+
+#### `POST /api/sessions/bulk`
+
+- **Auth:** Required
+- **Action:** Performs a bulk operation on multiple sessions
+- **Body:** `{ "action": "archive" | "unarchive" | "delete", "ids": [1, 2, 3] }`
+- **Constraints:**
+  - For `archive` and `delete`: rejects request with 400 if any session ID in the list is still active, returning the offending IDs in the error response
+  - All IDs must exist (404 if any are not found)
+  - Runs inside a database transaction — all-or-nothing
+- **Validation:** Returns 400 if `ids` is empty, if `action` is not one of the three valid values, or if `ids` is not an array
+- **Response:** `{ success: true, affected: <count> }`
+- **Route registration:** Must be registered before `/:id` routes to avoid Express matching `"bulk"` as an `:id` parameter
+
+### Modified Endpoint
+
+#### `GET /api/sessions`
+
+Add two query parameters:
+
+- **`filter`**: `"default"` | `"archived"` | `"all"`
+  - `"default"` (when omitted): returns sessions where `archived = 0`
+  - `"archived"`: returns sessions where `archived = 1`
+  - `"all"`: returns all sessions regardless of archived status
+- **`limit`**: `"5"` | `"10"` | `"25"` | `"50"` | `"all"`
+  - `"5"` (when omitted): returns the first 5 sessions (ordered by `created_at DESC`)
+  - `"all"`: no limit applied
+  - Any other value: applied as SQL `LIMIT`
+
+The response shape stays the same (array of session objects). Each session now includes the `archived` field (0 or 1). The existing `has_notes` and `notes_preview` fields continue as-is.
+
+**Total count:** The response should also include a way for the frontend to know how many sessions match the current filter (for the "N sessions total" display). Two options: a response header, or wrapping the response. To avoid breaking the existing array response shape, add a custom response header `X-Total-Count` with the total matching count before limit is applied.
+
+### Unchanged Endpoints
+
+- `GET /api/sessions/:id` — already returns the full session object; will naturally include `archived` once the column exists
+- `POST /api/sessions` — unchanged (new sessions default to `archived = 0`)
+- `POST /api/sessions/:id/close` — unchanged
+- `DELETE /api/sessions/:id` — unchanged (still works, used by detail page)
+- `PUT /api/sessions/:id/notes`, `DELETE /api/sessions/:id/notes` — unchanged
+
+## Frontend
+
+### History Page — Controls Bar
+
+Replace the existing "Show All / Show Recent" toggle with a cohesive controls bar containing:
+
+1. **Filter dropdown:** "Sessions" (default, `filter=default`), "Archived" (`filter=archived`), "All" (`filter=all`)
+2. **Show dropdown:** 5 (default), 10, 25, 50, All
+3. **Session count:** "N sessions total" — derived from the `X-Total-Count` response header
+4. **Select button** (admin only): toggles multi-select mode on/off
+
+Both the Filter and Show selections are persisted in `localStorage`:
+- `history-filter` — stores the selected filter value (`"default"`, `"archived"`, `"all"`)
+- `history-show-limit` — stores the selected limit value (`"5"`, `"10"`, `"25"`, `"50"`, `"all"`)
+
+Values are read on mount and written on change. The frontend should always pass both `filter` and `limit` query params explicitly when calling `GET /api/sessions`, including in the 3-second polling interval.
+
+### History Page — Session Cards
+
+#### Sunday Badge
+
+Sessions whose `created_at` falls on a Sunday (in the user's local timezone) display:
+- An amber "GAME NIGHT" badge (with sun icon) next to the session number
+- "· Sunday" appended to the date line in muted text
+
+Determination is client-side: `parseUTCTimestamp(session.created_at).getDay() === 0` using the existing `dateUtils.js` helper.
+
+#### Archived Badge
+
+When viewing the "All" or "Archived" filter, archived sessions show a gray "Archived" badge next to the session number.
+
+#### Notes Preview
+
+Continues as-is — indigo left-border teaser when `has_notes` is true.
+
+### History Page — Multi-Select Mode
+
+**Entering multi-select:**
+- Click the "Select" toggle button in the controls bar (admin only)
+- Long-press (500ms+) on a closed session card (admin only) — enters multi-select and selects that card
+
+**While in multi-select:**
+- Checkboxes appear on each session card
+- Active sessions (`is_active = 1`) are greyed out with a disabled checkbox — not selectable
+- Clicking a card toggles its selection (instead of navigating to detail page)
+- The "End Session" button on active session cards is hidden
+- A floating action bar appears at the bottom with:
+  - Left: "N selected" count
+  - Right: context-aware action buttons:
+    - **"Sessions" filter:** Archive + Delete
+    - **"Archived" filter:** Unarchive + Delete
+    - **"All" filter:** Archive + Unarchive + Delete
+- The action bar only appears when at least 1 session is selected
+- **Delete** always shows a confirmation modal: "Delete N sessions? This cannot be undone."
+- **Archive/Unarchive** execute immediately (non-destructive, reversible) with a toast confirmation
+
+**Changing filter or limit while in multi-select:**
+- Clears all selections (since the visible session list changes)
+- Stays in multi-select mode
+
+**Exiting multi-select:**
+- Click the "Done" / Select toggle button
+- Clears all selections and hides checkboxes + action bar
+
+### Session Detail Page
+
+#### Archive/Unarchive Button
+
+- Placed alongside the existing Delete Session button at the bottom of the page
+- Only visible to authenticated admins, only for closed sessions
+- Shows "Archive" if `session.archived === 0`, "Unarchive" if `session.archived === 1`
+- Executes immediately with toast confirmation (no modal — it's reversible)
+
+#### Archived Banner
+
+- When viewing an archived session, a subtle banner appears at the top of the detail content: "This session is archived"
+- Includes an inline "Unarchive" button (admin only)
+
+#### Sunday Badge
+
+- Same amber "GAME NIGHT" badge shown next to "Session #N" in the page header
+- "· Sunday" in the date/time display
+
+### Frontend Utilities
+
+Add a helper to `dateUtils.js`:
+
+```js
+export function isSunday(sqliteTimestamp) {
+  return parseUTCTimestamp(sqliteTimestamp).getDay() === 0;
+}
+```
+
+## What's NOT Changing
+
+- **Database:** No new tables, just one column addition
+- **Session notes** (view/edit/delete) — untouched
+- **EndSessionModal** — untouched
+- **WebSocket events** — no archive-related real-time updates
+- **Other routes/pages** (Home, Picker, Manager, Login) — untouched
+- **`POST /sessions/:id/close`** — untouched
+- **New dependencies** — none required (no new npm packages)