docs: record verified Linux packages and startup limits

PLAN.md

@@ -18,6 +18,9 @@
 - [ ] Cold install / repair / update / game exit на чистых Windows/Linux/macOS.
   Unit tests и web preview не заменяют эти прогоны.
 - [x] Native самообновление, русский UX, pinned updater key и защищённый release pipeline.
+- [x] Локальные AppImage/deb собраны на Ubuntu 26.04 с CI test key; подписи и
+  форматы проверены. Настоящий AppImage прошёл изолированный startup/lock/marker
+  smoke. Это не проверка установки, самообновления или совместимости Ubuntu 22.04.
 - [ ] Настроить защищённое GitHub environment/production secrets, опубликовать первый
   updater-релиз и проверить реальную замену приложения на каждой ОС. Подпись ОС и
   Apple notarization — отдельные настройки; CI test keys не предназначены игрокам.

docs/updater-release.md

@@ -281,3 +281,27 @@ Linux draft/publish verifier rechecks their container headers and signatures.
 Header/metadata inspection is not a runtime, architecture-emulation or installer
 migration test. Synthetic header fixtures exercise these checks; they are never
 installed or executed.
+
+
+## Local package verification, 2026-09-09
+
+Application source `696c6b0` was built on Ubuntu 26.04 x86_64 using a disposable
+CI updater key and the visible test-build flag. Actual AppImage and deb packages
+passed the same collection checks used by the workflow: expected container,
+architecture/version where represented, and cryptographic updater signatures.
+The manual-package collector explicitly signs deb/DMG even when a CLI version
+also emits their signatures. No production package or release was signed.
+
+The actual AppImage was started with `--appimage-extract-and-run`, isolated XDG
+roots and a pending update targeting a different version. The native executable
+ran inside its own `APPDIR/usr/bin/shacraft-launcher`, referenced the expected
+`APPIMAGE`, held the instance OS lock and preserved the pending marker during
+startup and after termination. This checks native startup and the runtime binding;
+it does not establish visual/IPC behavior, installation, self-replacement or a
+successful updater restart. The deb was inspected, not installed.
+
+This local Ubuntu 26.04 build is not a compatibility result for Ubuntu 22.04 or
+other distributions. The four-platform GitHub matrix, real Windows/macOS
+installations, old-version migration and end-to-end update acceptance remain
+pending. Production signing credentials and release environments are not
+configured on GitHub, and no release has been published.

scripts/release.py

@@ -250,7 +250,7 @@ def collect(root, bundle, destination, platform, version):
             )
             shutil.copyfile(source_signature, signature)
         else:
-            signer(root, target)  # Tauri does not produce deb/DMG updater signatures.
+            signer(root, target)  # Sign manual packages explicitly, independent of bundler output.
         verify_signature(root, target, signature)
     if os.environ.get("SHACRAFT_UPDATER_TEST_BUILD") == "1":
         (destination / "CI_NOT_FOR_RELEASE.txt").write_text(