fix(install): detect arch-suffixed desktop builds on repair/upgrade reruns (#94703)

electron-builder names the unpacked output <os>-unpacked on x64 and
<os>-<arch>-unpacked elsewhere (linux-arm64-unpacked, win-arm64-unpacked).
install.sh desktop_product_present and install.ps1
Test-DesktopProductPresent only listed the x64 names, so a rerun on an
ARM64 desktop install skipped the desktop rebuild and left a bundle built
from the previous code. List every unpacked dir main_desktop.py already
resolves, in both installers.

scripts/install.ps1

@@ -978,8 +978,12 @@ function Test-DesktopProductPresent {
     # upgrade rerun on a desktop install must REBUILD it rather than leave a
     # bundle built by the previous code: the app is part of that install and its
     # artifacts live inside the tree, so an update makes them stale, not gone.
+    # electron-builder suffixes the output dir with the arch on every non-x64
+    # target (win-arm64-unpacked, linux-arm64-unpacked, mac-arm64), so the x64
+    # names alone miss a desktop build on ARM64 (#94703).
     $release = Join-Path $InstallDir "apps/desktop/release"
-    foreach ($candidate in @("win-unpacked", "linux-unpacked", "mac", "mac-arm64")) {
+    foreach ($candidate in @("win-unpacked", "win-ia32-unpacked", "win-arm64-unpacked",
+                             "linux-unpacked", "linux-arm64-unpacked", "mac", "mac-arm64")) {
         if (Test-Path (Join-Path $release $candidate)) { return $true }
     }
     return $false

scripts/install.sh

@@ -612,9 +612,15 @@ desktop_product_present() {
     # bundle built from the previous code: the app is part of that install, and
     # the artifacts live inside the tree (gitignored), so an update makes them
     # stale instead of removing them.
-    local release="$INSTALL_DIR/apps/desktop/release"
-    [ -d "$release/linux-unpacked" ] || [ -d "$release/mac" ] \
-        || [ -d "$release/mac-arm64" ] || [ -d "$release/win-unpacked" ]
+    # electron-builder suffixes the output dir with the arch on every non-x64
+    # target (linux-arm64-unpacked, mac-arm64, win-arm64-unpacked), so the x64
+    # names alone miss a desktop build on ARM64 Linux/Windows (#94703).
+    local release="$INSTALL_DIR/apps/desktop/release" dir
+    for dir in linux-unpacked linux-arm64-unpacked mac mac-arm64 \
+               win-unpacked win-ia32-unpacked win-arm64-unpacked; do
+        [ -d "$release/$dir" ] && return 0
+    done
+    return 1
 }
 
 append_shell_path() {

tests/scripts/install/test_install_desktop_product_present.py

@@ -0,0 +1,50 @@
+"""Installer repair/upgrade reruns detect a built desktop app on every arch (#94703).
+
+electron-builder names the unpacked output ``<os>-unpacked`` on x64 but
+``<os>-<arch>-unpacked`` elsewhere (``linux-arm64-unpacked``,
+``win-arm64-unpacked``; macOS uses ``mac-arm64``). install.sh and install.ps1
+only knew the x64 names, so a rerun on an ARM64 desktop install skipped the
+desktop rebuild and left a bundle built from the previous code.
+"""
+from __future__ import annotations
+
+import os
+import re
+import shlex
+import subprocess
+from pathlib import Path
+
+import pytest
+
+ROOT = Path(__file__).resolve().parents[3]
+INSTALL_SH = ROOT / "scripts" / "install.sh"
+INSTALL_PS1 = ROOT / "scripts" / "install.ps1"
+
+UNPACKED_DIRS = ("linux-unpacked", "linux-arm64-unpacked", "mac", "mac-arm64",
+                 "win-unpacked", "win-ia32-unpacked", "win-arm64-unpacked")
+
+
+def _desktop_product_present(tmp_path: Path) -> int:
+    env = dict(os.environ, HOME=tmp_path.as_posix(), HERMES_HOME=(tmp_path / "home").as_posix(),
+               HERMES_INSTALL_DIR=(tmp_path / "install").as_posix())
+    script = f"source {shlex.quote(INSTALL_SH.as_posix())} --manifest >/dev/null\ndesktop_product_present\n"
+    return subprocess.run(["bash", "-c", script], env=env, capture_output=True, text=True, timeout=30).returncode
+
+
+@pytest.mark.parametrize("unpacked", UNPACKED_DIRS)
+def test_install_sh_detects_desktop_build(tmp_path, unpacked):
+    (tmp_path / "install" / "apps" / "desktop" / "release" / unpacked).mkdir(parents=True)
+    assert _desktop_product_present(tmp_path) == 0
+
+
+def test_install_sh_without_desktop_build(tmp_path):
+    (tmp_path / "install" / "apps" / "desktop" / "release" / "builder-debug").mkdir(parents=True)
+    assert _desktop_product_present(tmp_path) != 0
+
+
+def test_install_ps1_candidates_match_install_sh():
+    body = INSTALL_PS1.read_text(encoding="utf-8")
+    fn = body[body.index("function Test-DesktopProductPresent"):]
+    listed = re.search(r"foreach \(\$candidate in @\((.*?)\)\)", fn, re.S)
+    assert listed, "Test-DesktopProductPresent candidate list not found"
+    assert set(re.findall(r'"([^"]+)"', listed.group(1))) == set(UNPACKED_DIRS)