feat: add booking management, Open Day, unified signup modal

- MC registrations: notification toggles (confirm/remind) with urgency
- Group bookings: save to DB from BookingModal, admin CRUD at /admin/bookings
- Open Day: full event system with schedule grid (halls × time), per-class
  booking, discount pricing (30 BYN / 20 BYN from 3+), auto-cancel threshold
- Unified SignupModal replaces 3 separate forms — consistent fields
  (name, phone, instagram, telegram), Instagram DM fallback on network error
- Centralized /admin/bookings page with 3 tabs (classes, MC, Open Day),
  collapsible sections, notification toggles, filter chips
- Unread booking badge on sidebar + dashboard widget with per-type breakdown
- Pricing: contact hint (Instagram/Telegram/phone) on price & rental tabs,
  admin toggle to show/hide
- DB migrations 5-7: group_bookings table, open_day tables, unified fields

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -25,23 +25,25 @@ Content language: Russian
 src/
 ├── app/
 │   ├── layout.tsx          # Root layout, fonts, metadata
-│   ├── page.tsx            # Landing: Hero → About → Team → Classes → MasterClasses → Schedule → Pricing → News → FAQ → Contact
+│   ├── page.tsx            # Landing: Hero → [OpenDay] → About → Team → Classes → MasterClasses → Schedule → Pricing → News → FAQ → Contact
 │   ├── globals.css         # Tailwind imports
 │   ├── styles/
 │   │   ├── theme.css       # Theme variables, semantic classes
 │   │   └── animations.css  # Keyframes, scroll reveal, modal animations
 │   ├── admin/
-│   │   ├── page.tsx        # Dashboard with 11 section cards
+│   │   ├── page.tsx        # Dashboard with 13 section cards
 │   │   ├── login/          # Password auth
-│   │   ├── layout.tsx      # Sidebar nav shell
-│   │   ├── _components/    # SectionEditor, FormField, ArrayEditor
+│   │   ├── layout.tsx      # Sidebar nav shell (14 items)
+│   │   ├── _components/    # SectionEditor, FormField, ArrayEditor, NotifyToggle
 │   │   ├── meta/           # SEO editor
 │   │   ├── hero/           # Hero editor
 │   │   ├── about/          # About editor
 │   │   ├── team/           # Team list + [id] editor
 │   │   ├── classes/        # Classes editor with icon picker
-│   │   ├── master-classes/ # MC editor with registrations
+│   │   ├── master-classes/ # MC editor with registrations + notification toggles
+│   │   ├── open-day/       # Open Day event editor (settings + grid + bookings)
 │   │   ├── schedule/       # Schedule editor
+│   │   ├── bookings/       # Group booking management with notification toggles
 │   │   ├── pricing/        # Pricing editor
 │   │   ├── faq/            # FAQ editor
 │   │   ├── news/           # News editor
@@ -55,9 +57,15 @@ src/
 │       │   ├── team/[id]/      # GET/PUT/DELETE single member
 │       │   ├── team/reorder/   # PUT reorder
 │       │   ├── upload/         # POST file upload (whitelisted folders)
-│       │   ├── mc-registrations/ # CRUD registrations
+│       │   ├── mc-registrations/ # CRUD registrations + notification toggle
+│       │   ├── group-bookings/ # CRUD group bookings + notification toggle
+│       │   ├── open-day/       # CRUD events
+│       │   ├── open-day/classes/ # CRUD event classes
+│       │   ├── open-day/bookings/ # CRUD event bookings + notification toggle
 │       │   └── validate-instagram/ # GET check username
-│       └── master-class-register/ # POST public signup
+│       ├── master-class-register/ # POST public MC signup
+│       ├── group-booking/    # POST public group booking
+│       └── open-day-register/ # POST public Open Day booking
 ├── components/
 │   ├── layout/
 │   │   ├── Header.tsx      # Sticky nav, mobile menu, booking modal ("use client")
@@ -68,6 +76,7 @@ src/
 │   │   ├── Team.tsx        # Carousel + profile view
 │   │   ├── Classes.tsx     # Showcase layout with icon selector
 │   │   ├── MasterClasses.tsx # Cards with signup modal
+│   │   ├── OpenDay.tsx      # Open Day schedule grid + booking (conditional)
 │   │   ├── Schedule.tsx    # Day/group views with filters
 │   │   ├── Pricing.tsx     # Tabs: prices, rental, rules
 │   │   ├── News.tsx        # Featured + compact articles
@@ -76,8 +85,9 @@ src/
 │   └── ui/
 │       ├── Button.tsx
 │       ├── SectionHeading.tsx
-│       ├── BookingModal.tsx     # Booking form → Instagram DM
+│       ├── BookingModal.tsx     # Booking form → Instagram DM + DB save
 │       ├── MasterClassSignupModal.tsx # MC registration form → API
+│       ├── OpenDaySignupModal.tsx # Open Day class booking → API
 │       ├── NewsModal.tsx        # News detail popup
 │       ├── Reveal.tsx           # Intersection Observer scroll reveal
 │       ├── BackToTop.tsx
@@ -87,10 +97,11 @@ src/
 ├── lib/
 │   ├── constants.ts        # BRAND constants, NAV_LINKS
 │   ├── config.ts           # UI_CONFIG (thresholds, counts)
-│   ├── db.ts               # SQLite DB, migrations, CRUD
+│   ├── db.ts               # SQLite DB, 6 migrations, CRUD for all tables
 │   ├── auth.ts             # Token signing (Node.js)
 │   ├── auth-edge.ts        # Token verification (Edge/Web Crypto)
-│   └── content.ts          # getContent() — DB with fallback
+│   ├── content.ts          # getContent() — DB with fallback
+│   └── openDay.ts          # getActiveOpenDay() — server-side Open Day loader
 ├── proxy.ts                # Middleware: auth guard for /admin/*
 └── types/
     ├── index.ts
@@ -119,7 +130,10 @@ src/
 - Cookie: `bh-admin-token` (httpOnly, secure in prod)
 - Auto-save with 800ms debounce on all section editors
 - Team members: drag-reorder, photo upload, rich bio (experience, victories, education)
-- Master classes: slots, registration viewer, trainer/style autocomplete from existing data
+- Master classes: slots, registration viewer with notification tracking (confirm + reminder), trainer/style autocomplete
+- Group bookings: saved to DB from BookingModal, admin page at `/admin/bookings` with notification toggles
+- Open Day: event settings (date, pricing, discount rules, min bookings), schedule grid (halls × time slots), per-class booking with auto-cancel threshold, public section after Hero
+- Shared `NotifyToggle` component (`src/app/admin/_components/NotifyToggle.tsx`) used across MC registrations, group bookings, and Open Day bookings
 - File upload: whitelisted folders (`team`, `master-classes`, `news`, `classes`), max 5MB, image types only
 
 ## Security Notes
@@ -128,6 +142,10 @@ src/
 - API routes validate: input types, string lengths, numeric IDs
 - Public MC registration: length-limited but **no rate limiting yet** (add before production)
 
+## Upcoming Features
+- **Rate limiting** on public endpoints (`/api/master-class-register`, `/api/group-booking`, `/api/open-day-register`)
+- **DB backup mechanism** — automated/manual backup of `db/blackheart.db` with rotation
+
 ## AST Index
 - **Always use the AST index** at `memory/ast-index.md` when searching for components, props, hooks, types, or styles
 - Contains: component tree, all exports, props, hooks, client/server status, CSS classes, keyframes