M12e: contract pass (pair invite kind, admin name in invite links, sync failed flag, rejection actor, device version name, template id, update check result, untouched accounts, D-027 re-stamp, PushEvent in :core:model, snackbar hosts)

Server: E-3 invite_kind; E-12 link ?from=<admin name>, E-4 passes it into kvitt://invite;
X-Kvitt-App-Version-Name stored in devices.app_version_name (migration 0003, schema 3);
OpenAPI and examples follow. Phone: :core:model, :core:fakes, :data, features and :app
updated together; goldens re-recorded for S-20 (version name) and new S-1/S-22 states.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TQd3pEP9UeN2uifbHknQ7B

server/crates/kvitt-server/tests/skeleton/routes.rs

@@ -104,7 +104,7 @@ async fn health_reports_ok_with_versions() {
     assert_eq!(reply.status, StatusCode::OK);
     assert_eq!(
         reply.json,
-        json!({"status": "ok", "server_version": env!("CARGO_PKG_VERSION"), "schema_version": 2, "db_ok": true})
+        json!({"status": "ok", "server_version": env!("CARGO_PKG_VERSION"), "schema_version": 3, "db_ok": true})
     );
     assert_eq!(
         reply.headers["x-kvitt-server-version"],
@@ -124,7 +124,7 @@ async fn health_is_503_degraded_when_the_database_is_gone() {
     assert_eq!(reply.status, StatusCode::SERVICE_UNAVAILABLE);
     assert_eq!(reply.json["status"], "degraded");
     assert_eq!(reply.json["db_ok"], false);
-    assert_eq!(reply.json["schema_version"], 2);
+    assert_eq!(reply.json["schema_version"], 3);
 }
 
 #[tokio::test]
@@ -285,6 +285,44 @@ async fn last_seen_and_app_version_are_written_at_most_hourly() {
     assert!(parse_ts(&last_seen(&app).await.0).is_some());
 }
 
+async fn version_name(app: &TestApp) -> Option<String> {
+    sqlx::query_scalar("SELECT app_version_name FROM devices WHERE id = ?")
+        .bind(ADMIN_DEVICE_ID)
+        .fetch_one(&app.state.db)
+        .await
+        .unwrap()
+}
+
+fn with_version_name(path: &str, name: &str) -> Request<Body> {
+    let mut r = authed(Method::GET, path, &admin_token());
+    r.headers_mut()
+        .insert("x-kvitt-app-version-name", name.parse().unwrap());
+    r
+}
+
+#[tokio::test]
+async fn app_version_name_is_written_with_last_seen_and_bad_values_are_ignored() {
+    let app = TestApp::household().await;
+    app.send(with_version_name("/me", " 1.1 ")).await;
+    assert_eq!(version_name(&app).await.as_deref(), Some("1.1"));
+
+    let start = app.clock.now();
+    app.clock.set(start + Duration::minutes(59));
+    app.send(with_version_name("/me", "1.2")).await;
+    assert_eq!(version_name(&app).await.as_deref(), Some("1.1"), "hourly");
+
+    // An over-long or blank value keeps the stored one; no header keeps it too.
+    app.clock.set(start + Duration::minutes(60));
+    app.send(with_version_name("/me", &"9".repeat(33))).await;
+    assert_eq!(version_name(&app).await.as_deref(), Some("1.1"));
+    app.clock.set(start + Duration::minutes(120));
+    app.send(authed(Method::GET, "/me", &admin_token())).await;
+    assert_eq!(version_name(&app).await.as_deref(), Some("1.1"));
+    app.clock.set(start + Duration::minutes(180));
+    app.send(with_version_name("/me", "1.2")).await;
+    assert_eq!(version_name(&app).await.as_deref(), Some("1.2"));
+}
+
 #[tokio::test]
 async fn json_bodies_map_rejections_to_error_codes() {
     async fn echo(ApiJson(v): ApiJson<Value>) -> String {