feat(push): smart push queueing with page-visibility fast path and app-ping/pong fallback

server/db.ts

@@ -21,6 +21,7 @@ export function initDB(config: AppConfig): void {
       endpoint TEXT PRIMARY KEY,
       p256dh TEXT NOT NULL,
       auth TEXT NOT NULL,
+      device_id TEXT,
       created_at TEXT DEFAULT (datetime('now')),
       last_used TEXT
     );
@@ -80,6 +81,13 @@ export function initDB(config: AppConfig): void {
     db.exec("ALTER TABLE session_reviews ADD COLUMN parent_adapter TEXT NOT NULL DEFAULT 'claude'");
   }
 
+  // Migration: add device_id column to push_subscriptions if missing
+  const pushInfo = db.pragma('table_info(push_subscriptions)') as { name: string }[];
+  if (!pushInfo.some(c => c.name === 'device_id')) {
+    db.exec("ALTER TABLE push_subscriptions ADD COLUMN device_id TEXT DEFAULT NULL");
+  }
+  db.exec("CREATE INDEX IF NOT EXISTS idx_push_device ON push_subscriptions(device_id)");
+
   // Migration: add end_anchor_message_id column to session_reviews if missing
   if (!reviewInfo.some(c => c.name === 'end_anchor_message_id')) {
     db.exec("ALTER TABLE session_reviews ADD COLUMN end_anchor_message_id TEXT DEFAULT NULL");
@@ -109,6 +117,7 @@ function getDB(): BetterSqlite3.Database {
 
 interface PreparedStatements {
   pushSubsSave: BetterSqlite3.Statement;
+  pushSubsRemoveByDevice: BetterSqlite3.Statement;
   pushSubsRemove: BetterSqlite3.Statement;
   pushSubsGetAll: BetterSqlite3.Statement;
   pushSubsMarkUsed: BetterSqlite3.Statement;
@@ -139,12 +148,16 @@ function stmts(): PreparedStatements {
     _stmts = {
       // push_subscriptions
       pushSubsSave: d.prepare(`
-        INSERT INTO push_subscriptions (endpoint, p256dh, auth)
-        VALUES (?, ?, ?)
+        INSERT INTO push_subscriptions (endpoint, p256dh, auth, device_id)
+        VALUES (?, ?, ?, ?)
         ON CONFLICT(endpoint) DO UPDATE SET
           p256dh = excluded.p256dh,
-          auth = excluded.auth
+          auth = excluded.auth,
+          device_id = excluded.device_id
       `),
+      pushSubsRemoveByDevice: d.prepare(
+        `DELETE FROM push_subscriptions WHERE device_id = ? AND endpoint != ?`
+      ),
       pushSubsRemove: d.prepare(
         `DELETE FROM push_subscriptions WHERE endpoint = ?`
       ),
@@ -243,13 +256,17 @@ export interface PushSubRow {
   endpoint: string;
   p256dh: string;
   auth: string;
+  device_id: string | null;
   created_at: string;
   last_used: string | null;
 }
 
 export const pushSubs = {
-  save(endpoint: string, p256dh: string, auth: string): void {
-    stmts().pushSubsSave.run(endpoint, p256dh, auth);
+  save(endpoint: string, p256dh: string, auth: string, deviceId: string | null): void {
+    stmts().pushSubsSave.run(endpoint, p256dh, auth, deviceId ?? null);
+    if (deviceId) {
+      stmts().pushSubsRemoveByDevice.run(deviceId, endpoint);
+    }
   },
 
   remove(endpoint: string): void {