Add Rust server

Owns the database, PIN rotation and all LiveKit token minting. Kiosk
registration, session-stable joins, admin auth, layouts, branding, media
uploads and the hosted installer script.

Claude-Session: https://claude.ai/code/session_01SS9F92jb51bMCRCKem6QtD

server/migrations/0001_init.sql

@@ -0,0 +1,49 @@
+CREATE TABLE IF NOT EXISTS admins (
+    id TEXT PRIMARY KEY,
+    email TEXT NOT NULL UNIQUE,
+    password_hash TEXT NOT NULL,
+    created_at INTEGER NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS kiosks (
+    id TEXT PRIMARY KEY,
+    name TEXT NOT NULL,
+    location TEXT NOT NULL DEFAULT '',
+    room_name TEXT NOT NULL UNIQUE,
+    hardware_id TEXT,
+    enrollment_token_hash TEXT,
+    kiosk_token_hash TEXT,
+    status TEXT NOT NULL DEFAULT 'offline',
+    last_seen_at INTEGER,
+    created_at INTEGER NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS kiosk_pins (
+    pin TEXT PRIMARY KEY,
+    kiosk_id TEXT NOT NULL REFERENCES kiosks(id) ON DELETE CASCADE,
+    issued_at INTEGER NOT NULL,
+    expires_at INTEGER NOT NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_kiosk_pins_kiosk ON kiosk_pins(kiosk_id, issued_at DESC);
+CREATE INDEX IF NOT EXISTS idx_kiosk_pins_expiry ON kiosk_pins(expires_at);
+
+CREATE TABLE IF NOT EXISTS kiosk_layouts (
+    kiosk_id TEXT PRIMARY KEY REFERENCES kiosks(id) ON DELETE CASCADE,
+    data TEXT NOT NULL,
+    updated_at INTEGER NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS sessions (
+    id TEXT PRIMARY KEY,
+    kiosk_id TEXT NOT NULL REFERENCES kiosks(id) ON DELETE CASCADE,
+    participant_id TEXT NOT NULL,
+    display_name TEXT NOT NULL,
+    role TEXT NOT NULL,
+    created_at INTEGER NOT NULL,
+    expires_at INTEGER NOT NULL,
+    revoked INTEGER NOT NULL DEFAULT 0
+);
+
+CREATE INDEX IF NOT EXISTS idx_sessions_kiosk ON sessions(kiosk_id);
+CREATE INDEX IF NOT EXISTS idx_sessions_expiry ON sessions(expires_at);