fix(marge): preserve STORED_MUSIC account in recents (fix replay INVALID_SOURCE)

Replaying a STORED_MUSIC media-server item from Recents failed with
INVALID_SOURCE: the served recent's <source> had an empty <username>, so the
speaker fell back to the provider id ("7") as the account and could not resolve
which media server to use.

Root cause: a media server's account ("<UDN>/0") is persisted in
SourceKey.Account, but Username is NOT persisted (SaveConfiguredSources writes
sourceKey.account, not username). prepareRecentItemParitySource and
formatRecentResponse emitted <username> straight from the now-empty Username
field. The /full path (mapToFullResponseSource) already falls back to
SourceKeyAccount; the recents builders did not.

Fix: add recentSourceUsername(src) that falls back to SourceKeyAccount when
Username is empty (TuneIn / Internet Radio / Local Internet Radio keep an empty
username for parity), used by both recent <source> builders. Regression test
drives the captured Bose_Lisa flow (sourceid-only recent POST) and asserts the
served <source><username> is the real UDN, never empty or the bare provider id.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

pkg/service/marge/marge.go

@@ -225,6 +225,27 @@ func (p presetParityXML) MarshalXML(e *xml.Encoder, start xml.StartElement) erro
 	return e.EncodeElement(Alias(p), start)
 }
 
+// recentSourceUsername returns the account/username to emit in a recent's
+// <source> block. The account (e.g. STORED_MUSIC's "<UDN>/0") is persisted in
+// SourceKey.Account, not Username, which does not round-trip through the
+// datastore — so fall back to SourceKeyAccount. Without this, STORED_MUSIC
+// media-server recents get an empty <username>, the speaker falls back to the
+// provider id (e.g. "7") as the account, and replay fails with INVALID_SOURCE.
+// Mirrors the fallback in mapToFullResponseSource; TuneIn / Internet Radio /
+// Local Internet Radio intentionally keep an empty username (parity).
+func recentSourceUsername(src *models.ConfiguredSource) string {
+	if src.Username != "" {
+		return src.Username
+	}
+
+	switch src.SourceKeyType {
+	case constants.ProviderTunein, constants.ProviderInternetRadio, constants.ProviderLocalInternetRadio:
+		return ""
+	}
+
+	return src.SourceKeyAccount
+}
+
 func prepareRecentItemParitySource(src *models.ConfiguredSource) *models.RecentItemParitySource {
 	sxml := &models.RecentItemParitySource{
 		ID:               src.ID,
@@ -234,7 +255,7 @@ func prepareRecentItemParitySource(src *models.ConfiguredSource) *models.RecentI
 		Name:             src.DisplayName,
 		SourceProviderID: src.SourceProviderID,
 		SourceName:       src.SourceName,
-		Username:         src.Username,
+		Username:         recentSourceUsername(src),
 		Credential: &models.RecentItemParityCredential{
 			Type:  src.Credential.Type,
 			Value: src.Credential.Value,
@@ -2118,7 +2139,7 @@ func formatRecentResponse(recentObj *models.ServiceRecent, matchingSrc *models.C
 			Name:             matchingSrc.DisplayName,
 			SourceProviderID: matchingSrc.SourceProviderID,
 			SourceName:       matchingSrc.SourceName,
-			Username:         matchingSrc.Username,
+			Username:         recentSourceUsername(matchingSrc),
 		}
 
 		if res.Source.Name == "TuneIn" || res.Source.Name == "LOCAL_INTERNET_RADIO" {

pkg/service/marge/recent_storedmusic_account_test.go

@@ -0,0 +1,89 @@
+package marge
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"testing"
+
+	"github.com/gesellix/bose-soundtouch/pkg/service/constants"
+	"github.com/gesellix/bose-soundtouch/pkg/service/datastore"
+)
+
+// TestRecent_StoredMusicKeepsAccount is a regression test for the recents-replay
+// bug: a STORED_MUSIC media server's account ("<UDN>/0") is persisted in
+// SourceKey.Account, not Username (which does not round-trip). The recent
+// <source> builders emitted Username verbatim, producing an empty <username>;
+// the speaker then fell back to the provider id (e.g. "7") as the account and
+// replaying the recent failed with INVALID_SOURCE.
+//
+// The speaker registers a recent by sourceid only (no account in the POST), so
+// the served recent's account must come from the matched source. This asserts
+// the served <source> carries the real UDN, and never the bare provider id.
+func TestRecent_StoredMusicKeepsAccount(t *testing.T) {
+	tmp, err := os.MkdirTemp("", "recent-storedmusic-*")
+	if err != nil {
+		t.Fatalf("temp dir: %v", err)
+	}
+
+	defer func() { _ = os.RemoveAll(tmp) }()
+
+	ds := datastore.NewDataStore(tmp)
+	account := "6919733"
+	device := "A81B6A536A98"
+
+	if mkErr := os.MkdirAll(ds.AccountDeviceDir(account, device), 0o755); mkErr != nil {
+		t.Fatalf("mkdir: %v", mkErr)
+	}
+
+	const udn = "4d696e69-444c-164e-9d41-72ecda78e4c1/0"
+
+	sm := strconv.Itoa(constants.StoredMusicProviderID)
+
+	srcID, err := AddSource(ds, account, udn, sm, "", "", "AfterTouch Test Library")
+	if err != nil {
+		t.Fatalf("add source: %v", err)
+	}
+
+	// The speaker POSTs a recent referencing the source by id only (matches the
+	// captured Bose_Lisa payload: no <source> account/username).
+	recXML := fmt.Sprintf(`<?xml version="1.0" encoding="UTF-8" ?><recent>`+
+		`<lastplayedat>2026-06-14T16:35:30+00:00</lastplayedat>`+
+		`<sourceid>%s</sourceid>`+
+		`<name>02 - The Raven</name>`+
+		`<location>1$4$1 TRACK</location>`+
+		`<contentItemType></contentItemType></recent>`, srcID)
+
+	postResp, err := AddRecent(ds, account, device, []byte(recXML))
+	if err != nil {
+		t.Fatalf("add recent: %v", err)
+	}
+
+	// 1. The POST response (formatRecentResponse) must carry the real account.
+	assertAccount(t, "AddRecent response", string(postResp), udn)
+
+	// 2. The served recents list (RecentsToXML) must carry it too.
+	served, err := RecentsToXML(ds, account, device)
+	if err != nil {
+		t.Fatalf("RecentsToXML: %v", err)
+	}
+
+	assertAccount(t, "RecentsToXML", string(served), udn)
+}
+
+func assertAccount(t *testing.T, what, xml, udn string) {
+	t.Helper()
+
+	if !strings.Contains(xml, "<username>"+udn+"</username>") {
+		t.Errorf("%s: expected <username>%s</username>; got:\n%s", what, udn, xml)
+	}
+
+	if strings.Contains(xml, "<username></username>") || strings.Contains(xml, "<username/>") {
+		t.Errorf("%s: STORED_MUSIC source has an empty <username> (account lost):\n%s", what, xml)
+	}
+
+	if strings.Contains(xml, "<username>7</username>") {
+		t.Errorf("%s: STORED_MUSIC username is the bare provider id, not the account:\n%s", what, xml)
+	}
+}