feat: add a platform-aware apps download page

Serve desktop and Android builds from the latest Gitea release on /download, and fix the desktop compile and CI flakes that blocked v1.3.0.

Co-authored-by: Cursor <cursoragent@cursor.com>

services/api/internal/appupdate/appupdate_test.go

@@ -16,6 +16,22 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
+func TestPickClientFiles(t *testing.T) {
+	files := pickClientFiles([]asset{
+		{Name: "pipu-music-1.3.0.apk", Size: 10},
+		{Name: "pipu-music-1.3.0.apk.sha256", Size: 65, URL: "https://gitea/sum"},
+		{Name: "pipu-music_1.3.0_x64-setup.exe", Size: 20},
+		{Name: "pipu-music_1.3.0_amd64.deb", Size: 11},
+		{Name: "pipu-music_1.3.0_amd64.AppImage", Size: 30},
+		{Name: "pipu-music_1.3.0_aarch64.dmg", Size: 40},
+	})
+	assert.Equal(t, "pipu-music-1.3.0.apk", files["android"].Name)
+	assert.Equal(t, "https://gitea/sum", files["android"].ChecksumURL)
+	assert.Equal(t, "pipu-music_1.3.0_x64-setup.exe", files["windows"].Name)
+	assert.Equal(t, "pipu-music_1.3.0_amd64.AppImage", files["linux"].Name)
+	assert.Equal(t, "pipu-music_1.3.0_aarch64.dmg", files["macos"].Name)
+}
+
 func TestVersionCode(t *testing.T) {
 	cases := map[string]int{"v0.6.1": 60_199, "1.2.0-rc.3": 1_020_003, "v10.0.0": 10_000_099}
 	for tag, want := range cases {
@@ -60,17 +76,18 @@ func TestLatestAndDownload(t *testing.T) {
 	require.NoError(t, err)
 	assert.Equal(t, "0.6.1", l.Version)
 	assert.Equal(t, 60_199, l.VersionCode)
-	assert.Equal(t, hex.EncodeToString(sum[:]), l.SHA256)
+	android := l.Files["android"]
+	assert.Equal(t, hex.EncodeToString(sum[:]), android.SHA256)
 
-	path, err := h.ensure(context.Background(), l)
+	path, err := h.ensure(context.Background(), android)
 	require.NoError(t, err)
 	got, _ := os.ReadFile(path)
 	assert.Equal(t, apk, got)
 
 	// Подменённый файл не пройдёт сверку.
 	require.NoError(t, os.Remove(path))
-	l.SHA256 = "00" + l.SHA256[2:]
-	_, err = h.ensure(context.Background(), l)
+	android.SHA256 = "00" + android.SHA256[2:]
+	_, err = h.ensure(context.Background(), android)
 	assert.ErrorContains(t, err, "checksum mismatch")
 	_, statErr := os.Stat(filepath.Join(dir, "pipu-music-0.6.1.apk"))
 	assert.True(t, os.IsNotExist(statErr))